Medical system and dressing for use under compression

ABSTRACT

In some illustrative examples, a bridge suitable for treating a tissue site may include a bridge sealing member and one or more bridge wicking layers. The bridge sealing member may extend along a length of the bridge, and may define an internal passageway in fluid communication between a receiving end of the bridge and a transmitting end of the bridge. The one or more bridge wicking layers may be disposed within the internal passageway of the bridge sealing member. Other apparatus, systems, and methods are disclosed.

INCORPORATION BY REFERENCE

This application incorporates by reference the following disclosures intheir entirety: U.S. Pat. No. 8,814,842, filed Mar. 11, 2011, titledDELIVERY-AND-FLUID-STORAGE BRIDGES FOR USE WITH REDUCED-PRESSURESYSTEMS; U.S. Patent Publication No. 2014/0012213, filed Dec. 14, 2012,titled RELEASABLE MEDICAL DRAPES; U.S. Patent Publication No.2015/0119833, filed Sep. 19, 2014, titled DRESSING WITH DIFFERENTIALLYSIZED PERFORATIONS.

RELATED APPLICATION

The present application is a divisional of U.S. patent application Ser.No. 15/356,063, entitled “MEDICAL SYSTEM AND DRESSING FOR USE UNDERCOMPRESSION,” filed 18 Nov. 2016, which claims the benefit, under 35 USC§ 119(e), of the filing of U.S. Provisional Patent Application Ser. No.62/257,903, entitled “MEDICAL SYSTEM WITH FLEXIBLE FLUID STORAGEBRIDGE,” filed 20 Nov. 2015, which is incorporated herein by referencefor all purposes.

FIELD

This application relates generally to medical treatment systems and,more particularly, but not by way of limitation, to dressings, systems,and methods that may be suitable for treating a tissue site.

BACKGROUND

Clinical studies and practice have shown that reducing pressure inproximity to a tissue site can augment and accelerate growth of newtissue at the tissue site. The applications of this phenomenon arenumerous, but have been proven particularly advantageous for treatingwounds. Regardless of the etiology of a wound, whether trauma, surgery,or another cause, proper care of the wound is important to the outcome.Treatment of wounds or other tissue with reduced pressure may becommonly referred to as “reduced-pressure therapy.” However, suchtreatment may also be known by other names including “negative-pressuretherapy,” “negative-pressure wound therapy,” “vacuum therapy,”“vacuum-assisted closure,” and “topical negative-pressure,” for example.Reduced-pressure therapy may provide a number of benefits, includingmigration of epithelial and subcutaneous tissues, improved blood flow,and micro-deformation of tissue at a tissue site. Together, thesebenefits can increase development of granulation tissue and reducehealing times. Improvements to therapy systems, components, andprocesses may benefit manufacturers, healthcare providers, and patients.

SUMMARY

In some illustrative, non-limiting examples, a bridge assembly fortreating a tissue site may include a storage bridge. The storage bridgemay include a receiving end and a transmitting end separated by alength. The storage bridge may include a bridge envelope, a bridgeabsorbent, and a bridge sealing member. The bridge envelope may extendalong the length of the storage bridge and may define an internalvolume. The bridge absorbent may be disposed within the internal volumeof the bridge envelope. The bridge absorbent may include a volume thatis less than the internal volume of the bridge envelope. The bridgesealing member may encapsulate the bridge envelope and may define aninternal passageway in fluid communication between the receiving end andthe transmitting end.

In some illustrative, non-limiting examples, a storage bridge fortreating a tissue site may include a receiving end and a transmittingend separated by a length. Further, the storage bridge may include abridge envelope, a bridge absorbent, and a bridge sealing member. Thebridge envelope may extend along the length of the storage bridge, andmay define an internal volume. Further, the bridge envelope may includea fluid acquisition surface and a fluid distribution surface positionedopposite the fluid acquisition surface. The fluid distribution surfacemay face the internal volume. The bridge absorbent may be disposedwithin the bridge envelope. At least a portion of the bridge absorbentmay be spaced apart from the fluid distribution surface of the bridgeenvelope. The bridge sealing member may encapsulate the bridge envelope,and may define an internal passageway in fluid communication between thereceiving end and the transmitting end.

In some illustrative, non-limiting examples, a storage bridge fortreating a tissue site may include a receiving end and a transmittingend separated by a length. Further, the storage bridge may include afirst bridge wicking layer, a second bridge wicking layer, a bridgeabsorbent, and a bridge sealing member. The first bridge wicking layermay extend along the length of the storage bridge, and may comprise afluid acquisition surface and a fluid distribution surface. The fluiddistribution surface may be positioned on an opposite side of the firstbridge wicking layer from the fluid acquisition surface. The secondbridge wicking layer may extend along the length of the storage bridge,and may comprise a fluid acquisition surface and a fluid distributionsurface. The fluid distribution surface may be positioned on an oppositeside of the second bridge wicking layer from the fluid acquisitionsurface. A periphery of the second bridge wicking layer may be coupledto a periphery of the first bridge wicking layer to define an internalvolume. The bridge absorbent may be disposed within the internal volumebetween the first bridge wicking layer and the second bridge wickinglayer. The fluid distribution surface of the first wicking layer and thesecond wicking layer may face the bridge absorbent. The bridge sealingmember may include a substantially liquid impermeable and vaporpermeable film. Further, the bridge sealing member may define aninternal passageway in fluid communication between the receiving end andthe transmitting end. The first bridge wicking layer and the secondbridge wicking layer may be disposed within the internal passageway.

In some illustrative, non-limiting examples, a system for treating atissue site may include a dressing, a storage bridge, a conduitinterface, and a reduced-pressure source. The dressing may be forpositioning at the tissue site, and may include a dressing sealingmember and a dressing wicking layer. The dressing sealing member may beadapted to provide a sealed space between the dressing sealing memberand the tissue site. The dressing wicking layer may be disposed in thesealed space. The storage bridge may include a receiving end and atransmitting end separated by a length. The transmitting end may beadapted to be fluidly coupled to the dressing. Further, the storagebridge may include a bridge envelope, a bridge absorbent, and a bridgesealing member. The bridge envelope may extend along the length of thestorage bridge, and may define an internal volume. The bridge absorbentmay be disposed within the internal volume of the bridge envelope. Thebridge sealing member may encapsulate the bridge envelope. The conduitinterface may be adapted to be fluidly coupled to the receiving end ofthe storage bridge. Further, the conduit interface may be in fluidcommunication with the dressing through the storage bridge. Thereduced-pressure source may be adapted to be positioned in fluidcommunication with the conduit interface.

In some illustrative, non-limiting examples, a system for treating atissue site may include a dressing, a storage bridge, a conduitinterface, and a reduced-pressure source. The dressing may be forpositioning at the tissue site, and may include a dressing sealingmember and a dressing manifold. The dressing sealing member may beadapted to provide a sealed space between the dressing sealing memberand the tissue site. The dressing manifold may be disposed in the sealedspace. The storage bridge may include a receiving end and a transmittingend separated by a length. The transmitting end may be adapted to befluidly coupled to the dressing. Further, the storage bridge may includea bridge envelope, a bridge absorbent, and a bridge sealing member. Thebridge envelope may extend along the length of the storage bridge, andmay define an internal volume. The bridge absorbent may be disposedwithin the internal volume of the bridge envelope. The bridge sealingmember may encapsulate the bridge envelope. The conduit interface may beadapted to be fluidly coupled to the receiving end of the storagebridge. The conduit interface may be in fluid communication with thedressing through the storage bridge. The reduced-pressure source may beadapted to be positioned in fluid communication with the conduitinterface.

In some illustrative, non-limiting examples, a system for treating atissue site may include a dressing, a storage bridge, a conduitinterface, and a manual pump. The dressing may be for positioning at thetissue site, and may include a dressing sealing member and a dressingmanifold. The dressing sealing member may be adapted to provide a sealedspace between the dressing sealing member and the tissue site. Thedressing manifold may be disposed in the sealed space. The storagebridge may include a receiving end and a transmitting end separated by alength. The transmitting end may be adapted to be fluidly coupled to thedressing. Further, the storage bridge may include a bridge envelope, abridge absorbent, and a bridge sealing member. The bridge envelope mayextend along the length of the storage bridge, and may define aninternal volume. The bridge absorbent may be disposed within theinternal volume of the bridge envelope. The bridge absorbent may have avolume that is at least 5 percent less than the internal volume of thebridge envelope. The bridge sealing member may encapsulate the bridgeenvelope. The conduit interface may be adapted to be fluidly coupled tothe receiving end of the storage bridge. The conduit interface may be influid communication with the dressing through the storage bridge. Themanual pump may be adapted to be positioned in fluid communication withthe conduit interface.

In some illustrative, non-limiting examples, a method of treating atissue site may include positioning a dressing at the tissue site.Further, the method may include fluidly coupling a transmitting end of astorage bridge to the dressing, and fluidly coupling a manual pump to areceiving end of the storage bridge. Further, the method may includemanually activating the manual pump to cause fluid to move from thetissue site to the storage bridge through the dressing. Further, themethod may include storing at least a portion of the fluid in thestorage bridge. At least a portion of the fluid may be a liquid.Further, the method may include indicating a level of the fluid storedin the storage bridge with a plurality of fluid capacity indicatorspositioned along a length of the storage bridge.

In some illustrative, non-limiting examples, a system for treating atissue site may include a dressing, a bridge, a conduit interface, and areduced-pressure source. The dressing may be for positioning at thetissue site, and may include a dressing sealing member and one or moredressing wicking layers. The dressing sealing member may be adapted toprovide a sealed space between the dressing sealing member and thetissue site. The one or more dressing wicking layers may be disposed inthe sealed space. The bridge may include a receiving end and atransmitting end separated by a length. The transmitting end may beadapted to be fluidly coupled to the dressing. Further, the bridge mayinclude a bridge sealing member, and one or more wicking members. Thebridge sealing member may extend along the length, and may define aninternal volume. The one or more bridge wicking layers may be disposedwithin the internal volume of the bridge sealing member. The conduitinterface may be adapted to be fluidly coupled to the receiving end ofthe bridge. The conduit interface may be in fluid communication with thedressing through the bridge. The reduced-pressure source may be adaptedto be positioned in fluid communication with the conduit interface.

In some examples, the bridge may additionally or alternatively include abridge absorbent disposed within the internal volume of the bridgesealing member. The one or more dressing wicking layers may include atleast a first dressing wicking layer, a second dressing wicking layer,and a third dressing wicking layer. In some embodiments, the one or moredressing wicking layers may include a first dressing wicking layer and asecond dressing wicking layer. In some examples, a peripheral portion ofthe first dressing wicking layer is coupled to a peripheral portion ofthe third dressing wicking layer providing a wicking layer enclosure.The dressing may additionally or alternatively include a base layer andan adhesive. The base layer may have a periphery surrounding a centralportion and a plurality of apertures disposed through the periphery andthe central portion. The adhesive may be in fluid communication with theplurality of apertures at least in the periphery of the base layer. Insome examples, the dressing sealing member may include a periphery and acentral portion. The periphery of the dressing sealing member may bepositioned proximate to the periphery of the base layer. The centralportion of the dressing sealing member and the central portion of thebase layer may define an enclosure. The one or more dressing wickinglayers may be disposed in the enclosure. The dressing may additionallyor alternatively include a base layer adapted to be positioned incontact with the tissue site. The base layer may include a non-adherentmesh. The one or more dressing wicking layers may be positioned betweenthe base layer and the dressing sealing member.

In some examples, the one or more bridge wicking layers may include afirst bridge wicking layer and a second bridge wicking layer. The firstbridge wicking layer may have a surface area that is greater than asurface area of the second bridge wicking layer. The first bridgewicking layer may have a density that is greater than a density of thesecond bridge wicking layer. The first bridge wicking layer may beadapted to be positioned underneath the second bridge wicking layer.

In some examples, the one or more bridge wicking layers may include afluid acquisition surface and a fluid distribution surface positionedopposite the fluid acquisition surface. The fluid distribution surfacemay face the internal volume of the bridge sealing member. The fluiddistribution surface may include a plurality of longitudinal fibersoriented substantially in a longitudinal direction along the length ofthe bridge. The fluid acquisition surface may include a plurality ofvertical fibers oriented substantially normal relative to thelongitudinal fibers. The bridge sealing member may sealingly enclose theone or more bridge wicking layers between the receiving end and thetransmitting end of the bridge. The bridge sealing member may include asubstantially liquid impermeable and vapor permeable film. The systemmay additional or alternatively include a sealing apparatus adapted tobe positioned about a transmitting end aperture and between thetransmitting end and the dressing.

In some illustrative, non-limiting examples, a system for treating atissue site may include a dressing, a bridge, a conduit interface, and areduced-pressure source. The dressing may be for positioning at thetissue site, and may include a dressing sealing member and a dressingmanifold. The dressing sealing member may be adapted to provide a sealedspace between the dressing sealing member and the tissue site. Thedressing manifold may be disposed in the sealed space. The bridge mayinclude a receiving end and a transmitting end separated by a length.The transmitting end may be adapted to be fluidly coupled to thedressing. Further, the bridge may include a bridge sealing member, andone or more wicking members. The bridge sealing member may extend alongthe length, and may define an internal volume. The one or more bridgewicking layers may be disposed within the internal volume of the bridgesealing member. The conduit interface may be adapted to be fluidlycoupled to the receiving end of the bridge. The conduit interface may bein fluid communication with the dressing through the bridge. Thereduced-pressure source may be adapted to be positioned in fluidcommunication with the conduit interface.

In some illustrative, non-limiting examples, a system for treating atissue site may include a dressing, a bridge, a conduit interface, and amanual pump. The dressing may be for positioning at the tissue site, andmay include a dressing sealing member and one or more dressing wickinglayers. The dressing sealing member may be adapted to provide a sealedspace between the dressing sealing member and the tissue site. The oneor more dressing wicking layers may be disposed in the sealed space. Thebridge may include a receiving end and a transmitting end separated by alength. The transmitting end may be adapted to be fluidly coupled to thedressing. Further, the bridge may include a bridge sealing member, andone or more wicking members. The bridge sealing member may extend alongthe length, and may define an internal volume. The one or more bridgewicking layers may be disposed within the internal volume of the bridgesealing member. The conduit interface may be adapted to be fluidlycoupled to the receiving end of the bridge. The conduit interface may bein fluid communication with the dressing through the bridge. The manualpump may be adapted to be positioned in fluid communication with theconduit interface.

In some illustrative, non-limiting examples, a method of treating atissue site may include positioning a dressing at the tissue site.Further, the method may include fluidly coupling a transmitting end of abridge to the dressing, and fluidly coupling a manual pump to areceiving end of the bridge. Further, the method may include manuallyactivating the manual pump to cause fluid to move from the tissue siteto the bridge through one or more dressing wicking layers of thedressing and to cause fluid to move through one or more bridge wickinglayers of the bridge to the manual pump. Further, the method may includestoring at least a portion of the fluid in the manual pump. At least aportion of the fluid may be a liquid.

In some illustrative, non-limiting examples, a bridge assembly fortreating a tissue site may include a bridge. The bridge may include areceiving end and a transmitting end separated by a length. The bridgemay include a bridge sealing member, and one or more bridge wickinglayers. The bridge sealing member may extend along the length of thebridge and may define an internal passageway in fluid communicationbetween the receiving end and the transmitting end. The one or morebridge wicking layers may be disposed within the internal passageway.The one or more bridge wicking layers may be configured to communicatefluid between the receiving end and the transmitting end of the bridge.

In some examples, the bridge assembly may alternatively or additionallyinclude a bridge absorbent disposed within the internal passageway. Thebridge absorbent may include a volume that is less than a volume of theinternal passageway. The bridge assembly may alternatively oradditionally include a conduit interface adapted to be fluidly coupledto the receiving end of the bridge. The conduit interface may be influid communication with the transmitting end through the bridge. Thebridge assembly may alternatively or additionally include a fluidcapacity indicator positioned along the length of the bridge. The bridgesealing member may encapsulate the one or more bridge wicking layers.The bridge sealing member may include a non-woven material. The one ormore bridge wicking layers may be moveable within the internalpassageway.

The one or more bridge wicking layers may include a first bridge wickinglayer, a second bridge wicking layer, a third bridge wicking layer. Aperiphery of the first bridge wicking layer may be coupled to aperiphery of the third bridge wicking layer. The second bridge wickinglayer may be positioned between the first bridge wicking layer and thethird bridge wicking layer. Each of the one or more bridge wickinglayers may be comprised of a non-woven material. Each of the one or morebridge wicking layers may include a fluid acquisition surface and afluid distribution surface positioned opposite the fluid acquisitionsurface. The fluid distribution surface of each of the one or morebridge wicking layers may face a first direction. The fluid acquisitionsurface of each of the one or more bridge wicking layers may face asecond direction. The bridge sealing member may entirely surround theone or more bridge wicking layers. The bridge sealing member may includea substantially liquid impermeable film. The bridge sealing member maybe a vapor permeable film. The bridge sealing member may include abreathable film. The bridge sealing member may include a first sealinglayer and a second sealing layer. A periphery of the first sealing layermay be coupled to a periphery of the second sealing layer around the oneor more bridge wicking layers.

In some examples, the one or more bridge wicking layers may include afirst bridge wicking layer and a second bridge wicking layer. The firstbridge wicking layer may have a surface area that is greater than asurface area of the second bridge wicking layer. The first bridgewicking layer may have a density that is greater than a density of thesecond bridge wicking layer. The first bridge wicking layer may beadapted to be positioned underneath the second bridge wicking layer.

In some illustrative, non-limiting examples, a bridge for treating atissue site may include a receiving end and a transmitting end separatedby a length. Further, the bridge may include a bridge sealing member,and one or more bridge wicking layers. The bridge sealing member mayextend along the length of the bridge, and may define an internalpassageway in fluid communication between the receiving end and thetransmitting end. Further, the bridge sealing member may include a firstsealing layer and a second sealing layer positioned opposite the firstsealing layer. The one or more bridge wicking layers may be disposedwithin the bridge sealing member. At least a portion of the one or morebridge wicking layers may be spaced apart from the bridge sealingmember. The one or more bridge wicking layers may include a first bridgewicking layer and a second bridge wicking layer. The first bridgewicking layer may have a surface area that is greater than a surfacearea of the second bridge wicking layer. The first bridge wicking layermay have a density that is greater than a density of the second bridgewicking layer. The first bridge wicking layer may be adapted to bepositioned underneath the second bridge wicking layer.

In some examples, the bridge may additionally or alternatively includean absorbent disposed within the bridge sealing member. At least aportion of the absorbent may be spaced apart from the first sealinglayer and the second sealing layer of the bridge sealing member. Thebridge sealing member may entirely surround the one or more bridgewicking layers. The one or more bridge wicking layers may include afirst bridge wicking layer, a second bridge wicking layer, and a thirdbridge wicking layer. A periphery of the first bridge wicking layer maybe coupled to a periphery of the third bridge wicking layer. The secondbridge wicking layer may be disposed between the first bridge wickinglayer and the third bridge wicking layer. Each of the one or more bridgewicking layers may include of a non-woven material. Each of the one ormore bridge wicking layers may include a fluid acquisition surface and afluid distribution surface positioned opposite the fluid acquisitionsurface. The fluid distribution surface of each of the one or morebridge wicking layers may face a first direction. The fluid acquisitionsurface of each of the one or more bridge wicking layers may face asecond direction. The bridge sealing member may include a substantiallyliquid impermeable and vapor permeable film.

In some illustrative, non-limiting examples, a bridge for treating atissue site may include a receiving end and a transmitting end separatedby a length. Further, the bridge may include a first set of one or morebridge wicking layers, a second set of one or more bridge wickinglayers, and a bridge sealing member. The first set of one or more bridgewicking layers may extend along the length of the bridge, and mayinclude a fluid acquisition surface and a fluid distribution surface.The fluid distribution surface may be positioned on an opposite side ofat least one bridge wicking layer of the first set of one or more bridgewicking layers from the fluid acquisition surface. The second set of oneor more bridge wicking layers may extend along the length of the storagebridge, and may include a fluid acquisition surface and a fluiddistribution surface. The fluid distribution surface may be positionedon an opposite side of at least one bridge wicking layer of the secondset of one or more bridge wicking layers from the fluid acquisitionsurface. A periphery of at least one bridge wicking layer of the secondset of one or more bridge wicking layers may be coupled to a peripheryof at least one bridge wicking layer of the first set of one or morebridge wicking layers to define an internal volume. The bridge sealingmember may include a substantially liquid impermeable and vaporpermeable film. Further, the bridge sealing member may define aninternal passageway in fluid communication between the receiving end andthe transmitting end. The first set of one or more bridge wicking layersand the second set of one or more bridge wicking layers may be disposedwithin the internal passageway.

In some embodiments, the bridge may alternatively or additionally abridge absorbent disposed within the internal volume between the firstset of one or more bridge wicking layers and the second set of one ormore bridge wicking layers. The fluid distribution surface of the atleast one bridge wicking layer of the first set of one or more bridgewicking layers and the at least one bridge wicking layer of the secondset of one or more bridge wicking layers may face the bridge absorbent.At least a portion of the bridge absorbent may be spaced apart from thefluid distribution surface of the at least one bridge wicking layer ofthe first set of one or more bridge wicking layers and the at least onebridge wicking layer of the second set of one or more bridge wickinglayers. The fluid distribution surface of the at least one bridgewicking layer of the first set of one or more bridge wicking layers andthe at least one bridge wicking layer of the second set of one or morebridge wicking layers may include a plurality of longitudinal fibersoriented substantially in a longitudinal direction along the length. Thefluid acquisition surface of the at least one bridge wicking layer ofthe first set of one or more bridge wicking layers and the at least onebridge wicking layer of the second set of one or more bridge wickinglayers may include a plurality of vertical fibers oriented substantiallynormal relative to the longitudinal fibers.

In some illustrative, non-limiting examples, a bridge for treating atissue site may include a receiving end and a transmitting end separatedby a length. Further, the bridge may include a first bridge wickinglayer, a second bridge wicking layer, and a bridge sealing member. Thefirst bridge wicking layer may extend along the length of the bridge,and may include a fluid acquisition surface and a fluid distributionsurface. The fluid distribution surface may be positioned on an oppositeside of the first bridge wicking layer from the fluid acquisitionsurface. The second bridge wicking layer may extend along the length ofthe storage bridge, and may include a fluid acquisition surface and afluid distribution surface. The fluid distribution surface may bepositioned on an opposite side of the second bridge wicking layer fromthe fluid acquisition surface. A periphery of the second bridge wickinglayer may be coupled to a periphery of the first bridge wicking layer todefine an internal volume. The bridge sealing member may include asubstantially liquid impermeable and vapor permeable film. Further, thebridge sealing member may define an internal passageway in fluidcommunication between the receiving end and the transmitting end. Thefirst bridge wicking layer and the second bridge wicking layer may bedisposed within the internal passageway.

In some embodiments, the bridge may alternatively or additionally abridge absorbent disposed within the internal volume between the firstbridge wicking layer and the second bridge wicking layer. The fluiddistribution surface of the first bridge wicking layer and the secondbridge wicking layer may face the bridge absorbent. At least a portionof the bridge absorbent may be spaced apart from the fluid distributionsurface of the first bridge wicking layer and the second bridge wickinglayer. The fluid distribution surface of the first bridge wicking layerand the second bridge wicking layer may include a plurality oflongitudinal fibers oriented substantially in a longitudinal directionalong the length. The fluid acquisition surface of the first bridgewicking layer and the second bridge wicking layer may include aplurality of vertical fibers oriented substantially normal relative tothe longitudinal fibers.

Other aspects, features, and advantages of the illustrative exampleswill become apparent with reference to the drawings and detaileddescription that follow.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cut-away view of an illustrative example of a system fortreating a tissue site depicting an illustrative example of a dressingdeployed at the tissue site;

FIG. 2 is a cut-away view of the dressing of FIG. 1 ;

FIG. 3 is detail view taken at reference FIG. 3 , shown in FIG. 1 ,illustrating the dressing of FIG. 1 positioned proximate to tissuesurrounding the tissue site;

FIG. 4A is an exploded view of the dressing of FIG. 1 , depicted withouta conduit interface and with an illustrative example of a release linerfor protecting the dressing prior to application at the tissue site;

FIG. 4B is a plan view of an illustrative example of a base layerdepicted in the dressing of FIG. 4A;

FIG. 5 is a cut-away view of an illustrative example of a fluidmanagement assembly suitable for use with the dressing and system ofFIG. 1 ;

FIG. 6 is a cut-away view of another illustrative example of a fluidmanagement assembly suitable for use with the dressing and system ofFIG. 1 ;

FIG. 7 is a cut-away view of an illustrative example of a conduitinterface shown with the dressing of FIG. 1 ;

FIG. 8 is a cut-away view of another illustrative example of a dressingand a fluid management assembly suitable for use with the system of FIG.1 ;

FIG. 9 is a plan view of an illustrative example of a bridge assemblysuitable for use with the system and the dressing of FIG. 1 ;

FIG. 10 is a cross-section of an illustrative example of a storagebridge shown with the bridge assembly of FIG. 9 , taken at lines 10-10;

FIG. 11 is an exploded view of the bridge assembly of FIG. 9 ;

FIG. 12 is a graph illustrating reduced pressure communication to adressing through a bridge assembly according to this disclosure duringapplication of fluid to the dressing;

FIG. 13 is a cut-away view of an illustrative example of a system fortreating a tissue site depicting another illustrative example of adressing deployed at the tissue site;

FIG. 14 is a cut-away view of the dressing of FIG. 13 ;

FIG. 15 is a detail view taken at reference FIG. 15 , shown in FIG. 13 ,illustrating the dressing of FIG. 13 positioned proximate to tissuesurrounding the tissue site;

FIG. 16A is an exploded view of the dressing of FIG. 13 , depictedwithout a conduit interface and with an illustrative example of arelease liner for protecting the dressing prior to application at thetissue site;

FIG. 16B is a plan view of an illustrative example of a base layerdepicted in the dressing of FIG. 16A;

FIG. 17 is a cut-away view of an illustrative example of a fluidmanagement assembly suitable for use with the dressing and system ofFIG. 13 ;

FIG. 18 is a cut-away view of an illustrative example of a conduitinterface shown with the dressing of FIG. 13 ;

FIG. 19 is a cut-away view of another illustrative example of a dressingand a fluid management assembly suitable for use with the system of FIG.13 ;

FIG. 20 is a plan view of an illustrative example of a bridge assemblysuitable for use with the system and the dressing of FIG. 13 ;

FIG. 21 is a cross-section of an illustrative example of a bridge shownwith the bridge assembly of FIG. 20 , taken at lines 11-11; and

FIG. 22 is an exploded view of the bridge assembly of FIG. 20 .

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

In the following detailed description of illustrative exampleembodiments, reference is made to the accompanying drawings that form apart of this disclosure. Other embodiments may be used, and logical,structural, mechanical, electrical, and chemical changes may be madewithout departing from the scope of this disclosure. Further, thedescription may omit certain information known to those skilled in theart. Therefore, the following detailed description is non-limiting, andthe appended claims define the scope of the illustrative embodiments.Further, as used throughout this disclosure, “or” does not requiremutual exclusivity.

Referring to the drawings, FIG. 1 depicts an illustrative embodiment ofa system 102 for treating a tissue site 104 of a patient. The tissuesite 104 may extend through or otherwise involve an epidermis 106, adermis 108, and a subcutaneous tissue 110. The tissue site 104 may be asub-surface tissue site as depicted in FIG. 1 that may extend below thesurface of the epidermis 106. Further, the tissue site 104 may be asurface tissue site (not shown) that may predominantly reside on thesurface of the epidermis 106, such as, for example, an incision. Thesystem 102 may provide therapy to, for example, the epidermis 106, thedermis 108, and the subcutaneous tissue 110, regardless of thepositioning of the system 102 or the type of tissue site. The system 102may also be used without limitation at other tissue sites.

The tissue site 104 may be the bodily tissue of any human, animal, orother organism, including bone tissue, adipose tissue, muscle tissue,dermal tissue, vascular tissue, connective tissue, cartilage, tendons,ligaments, or any other tissue. Treatment of the tissue site 104 mayinclude the removal of fluids, such as exudate or ascites.

Continuing with FIG. 1 , the system 102 may include an optional tissueinterface, such as an interface manifold 120. Further, the system 102may include a dressing 124 and a reduced-pressure source 128. Thereduced-pressure source 128 may be a component of an optional therapyunit 130. In some embodiments, the reduced-pressure source 128 and thetherapy unit 130 may be separate components. Further, in someembodiments, the interface manifold 120 may be omitted for differenttypes of tissue sites or different types of therapy, such as, forexample, epithelialization. If equipped, the interface manifold 120 maybe adapted to be positioned proximate to or adjacent to the tissue site104, such as, for example, by cutting or otherwise shaping the interfacemanifold 120 in any suitable manner to fit the tissue site 104. Asdescribed below, the interface manifold 120 may be adapted to bepositioned in fluid communication with the tissue site 104 to distributereduced pressure to the tissue site 104. In some embodiments, theinterface manifold 120 may be positioned in direct contact with thetissue site 104.

The tissue interface or the interface manifold 120 may be formed fromany manifold material or flexible bolster material that provides avacuum space, or treatment space, such as, for example, a porous andpermeable foam or foam-like material, a member formed with pathways, agraft, or a gauze. In some embodiments, the interface manifold 120 maybe a reticulated, open-cell polyurethane or polyether foam that may befluid permeable while under a reduced pressure. One such foam materialis VAC® GranuFoam® material available from Kinetic Concepts, Inc. (KCI)of San Antonio, Tex. Further, in some embodiments, any material orcombination of materials may be used as a manifold material for theinterface manifold 120 provided that the manifold material is operableto distribute or collect fluid. For example, herein the term manifoldmay refer to a substance or structure configured for delivering fluidsto or removing fluids from a tissue site through a plurality of pores,pathways, or flow channels. The plurality of pores, pathways, or flowchannels may be interconnected to improve the distribution of fluidsprovided to and removed from an area around the manifold. Examples ofmanifolds may include, without limitation, devices that have structuralelements arranged to form flow channels, cellular foam, such asopen-cell foam, porous tissue collections, and liquids, gels, and foamsthat include or cure to include flow channels.

In some embodiments, a material with a higher or lower density thanGranuFoam® material may be desirable for the interface manifold 120depending on the application. Among the many possible materials, thefollowing may be used without limitation: GranuFoam® material; Foamex®technical foam (www.foamex.com); a molded bed of nails structure; apatterned grid material, such as those manufactured by Sercol IndustrialFabrics; 3D textiles, such as those manufactured by Baltex of Derby,U.K.; a gauze; a flexible channel-containing member; or a graft.Further, in some embodiments, ionic silver may be added to the interfacemanifold 120 by, for example, a micro bonding process. Other substances,such as anti-microbial agents, may be added to the interface manifold120 as well.

In some embodiments, the interface manifold 120 may comprise a porous,hydrophobic material. The hydrophobic characteristics of the interfacemanifold 120 may prevent the interface manifold 120 from directlyabsorbing fluid, such as exudate, from the tissue site 104, but allowthe fluid to pass through.

In some embodiments, the dressing 124 may include a base layer 132, anadhesive 136, a sealing member 140, a fluid management assembly 144, anda conduit interface 148. Components of the dressing 124 may be added orremoved to suit a particular application. In some embodiments, thedressing 124 may be adapted to provide reduced pressure from thereduced-pressure source 128 to the interface manifold 120, and toextract fluid from the tissue site 104 through the interface manifold120.

Referring to FIGS. 1-4B, the base layer 132 may have a periphery 152surrounding a central portion 156, and a plurality of apertures 160disposed through the periphery 152 and the central portion 156. The baselayer 132 may also have corners 158 and edges 159. The corners 158 andthe edges 159 may be part of the periphery 152. One of the edges 159 maymeet another of the edges 159 to define one of the corners 158. Further,the base layer 132 may have a border 161 substantially surrounding thecentral portion 156 and positioned between the central portion 156 andthe periphery 152. In some embodiments, the border 161 may be free ofthe apertures 160. In some embodiments, the base layer 132 may beadapted to cover the interface manifold 120 and tissue surrounding thetissue site 104 such that the central portion 156 of the base layer 132is positioned adjacent to or proximate to the interface manifold 120,and the periphery 152 of the base layer 132 is positioned adjacent to orproximate to tissue surrounding the tissue site 104. In suchembodiments, the periphery 152 of the base layer 132 may surround theinterface manifold 120. Further, the apertures 160 in the base layer 132may be in fluid communication with the interface manifold 120 and tissuesurrounding the tissue site 104.

The apertures 160 in the base layer 132 may have any shape, such as, forexample, circles, squares, stars, ovals, polygons, slits, complexcurves, rectilinear shapes, triangles, or other shapes. The apertures160 may be formed by cutting, by application of local RF energy, orother suitable techniques for forming an opening. Each of the apertures160 of the plurality of apertures 160 may be substantially circular inshape, having a diameter and an area. The area of the apertures 160described in the illustrative embodiments herein may be substantiallysimilar to the area in other embodiments for the apertures 160 that mayhave non-circular shapes. Further, the area of each of the apertures 160may be substantially the same, or each of the areas may vary, forexample, based on the position of the aperture 160 in the base layer132. For example, the area of the apertures 160 in the periphery 152 ofthe base layer 132 may be larger than the area of the apertures 160 inthe central portion 156 of the base layer 132. The apertures 160 mayhave a uniform pattern or may be randomly distributed on the base layer132. The size and configuration of the apertures 160 may be designed tocontrol the adherence of the dressing 124 to the epidermis 106 asdescribed below.

In some embodiments, the apertures 160 positioned in the periphery 152may be apertures 160 a, the apertures 160 positioned at the corners 158of the periphery 152 may be apertures 160 b, and the apertures 160positioned in the central portion 156 may be apertures 160 c. In someembodiments, the apertures 160 a may have an area greater than theapertures 160 b. Further, in some embodiments, the apertures 160 b mayhave an area greater than the apertures 160 c. The dimensions of thebase layer 132 may be increased or decreased, for example, substantiallyin proportion to one another to suit a particular application. Further,although the central portion 156, the border 161, and the periphery 152of the base layer 132 are shown as having a substantially square shape,these and other components of the base layer 132 may have any shape tosuit a particular application.

The base layer 132 may be a soft, pliable material suitable forproviding a fluid seal with the tissue site 104 as described herein. Forexample, the base layer 132 may comprise a silicone gel, a softsilicone, hydrocolloid, hydrogel, polyurethane gel, polyolefin gel,hydrogenated styrenic copolymer gel, a foamed gel, a soft closed cellfoam such as polyurethanes and polyolefins coated with an adhesive asdescribed below, polyurethane, polyolefin, or hydrogenated styreniccopolymers. In some embodiments, the base layer 132 may include asilicone such as Scapa Soft-Pro®. The base layer 132 may have athickness between about 500 microns (μm) and about 1000 microns (μm). Insome embodiments, the base layer 132 may have a stiffness between about5 Shore OO and about 80 Shore OO. Further, in some embodiments, the baselayer 132 may be comprised of hydrophobic or hydrophilic materials.

In some embodiments (not shown), the base layer 132 may be ahydrophobic-coated material. For example, the base layer 132 may beformed by coating a spaced material, such as, for example, woven,nonwoven, molded, or extruded mesh with a hydrophobic material. Thehydrophobic material for the coating may be a soft silicone, forexample. In this manner, the adhesive 136 may extend through openings inthe spaced material analogous to the apertures 160.

In some embodiments, the adhesive 136 may be exposed to the apertures160 in at least the periphery 152 of the base layer 132. Further, insome embodiments, the adhesive 136 may be positioned adjacent to, orpositioned in fluid communication with, the apertures 160 in at leastthe periphery 152 of the base layer 132. Further, in some embodiments,the adhesive 136 may be exposed to or in fluid communication with tissuesurrounding the tissue site 104 through the apertures 160 in the baselayer 132. As described further below and shown in FIG. 3 , the adhesive136 may extend, deform, or be pressed through the plurality of apertures160 to contact the epidermis 106 for securing the dressing 124 to, forexample, tissue surrounding the tissue site 104. The apertures 160 mayprovide sufficient contact of the adhesive 136 to the epidermis 106 tosecure the dressing 124 about the tissue site 104. However, theconfiguration of the apertures 160 and the adhesive 136, describedbelow, may permit release and repositioning of the dressing 124 aboutthe tissue site 104.

In some embodiments, the apertures 160 b at the corners 158 of theperiphery 152 may be smaller than the apertures 160 a in other portionsof the periphery 152. For a given geometry of the corners 158, thesmaller size of the apertures 160 b compared to the apertures 160 a mayenhance or increase the surface area of the adhesive 136 exposed to theapertures 160 b and to tissue through the apertures 160 b at the corners158. The size and number of the apertures 160 b in the corners 158 maybe adjusted as necessary, depending on the chosen geometry of thecorners 158, to enhance or increase the exposed surface area of theadhesive 136 as described above.

Similar to the apertures 160 b in the corners 158, any of the apertures160 may be adjusted in size and number to increase the surface area ofthe adhesive 136 exposed to or in fluid communication with the apertures160 for a particular application or geometry of the base layer 132. Forexample, in some embodiments (not shown) the apertures 160 b, orapertures of another size, may be positioned in the periphery 152 and atthe border 161. Similarly, the apertures 160 b, or apertures of anothersize, may be positioned as described above in other locations of thebase layer 132 that may have a complex geometry or shape.

The adhesive 136 may be a medically-acceptable adhesive. In someembodiments, the adhesive 136 may be deformable or flowable. Forexample, the adhesive 136 may comprise an acrylic adhesive, rubberadhesive, high-tack silicone adhesive, polyurethane, or other adhesivesubstance. In some embodiments, the adhesive 136 may be apressure-sensitive adhesive comprising an acrylic adhesive. The adhesive136 may be a layer having substantially the same shape as the periphery152 of the base layer 132. In some embodiments, the adhesive 136 may becontinuous or discontinuous. Discontinuities in the adhesive 136 may beprovided by apertures (not shown) in the adhesive 136. Apertures in theadhesive 136 may be formed after application of the adhesive 136 or bycoating the adhesive 136 in patterns on a carrier layer, such as, forexample, a side of the sealing member 140 adapted to face the epidermis106. Further, apertures in the adhesive 136 may be sized to control theamount of the adhesive 136 extending through the apertures 160 in thebase layer 132 to reach the epidermis 106. Apertures in the adhesive 136may also be sized to enhance the Moisture Vapor Transfer Rate (MVTR) ofthe dressing 124, described further below.

Factors that may be utilized to control the adhesion strength of thedressing 124 may include the diameter, area, and number of the apertures160 in the base layer 132, the thickness of the base layer 132, thethickness and amount of the adhesive 136, and the tackiness of theadhesive 136. An increase in the amount of the adhesive 136 extendingthrough the apertures 160 may correspond to an increase in the adhesionstrength of the dressing 124. A decrease in the thickness of the baselayer 132 may correspond to an increase in the amount of adhesive 136extending through the apertures 160. Thus, the diameter, area, andconfiguration of the apertures 160, the thickness of the base layer 132,and the amount and tackiness of the adhesive utilized may be varied toprovide a desired adhesion strength for the dressing 124.

In some embodiments, the tackiness of the adhesive 136 may vary indifferent locations of the base layer 132. For example, in locations ofthe base layer 132 where the apertures 160 are comparatively large, suchas the apertures 160 a, the adhesive 136 may have a lower tackiness thanother locations of the base layer 132 where the apertures 160 aresmaller, such as the apertures 160 b and 160 c. In this manner,locations of the base layer 132 having larger apertures 160 and lowertackiness adhesive 136 may have an adhesion strength comparable tolocations having smaller apertures 160 and higher tackiness adhesive136.

A release liner 162 may be attached to or positioned adjacent to thebase layer 132 to protect the adhesive 136 prior to application of thedressing 124 to the tissue site 104. Prior to application of thedressing 124 to the tissue site 104, the base layer 132 may bepositioned between the sealing member 140 and the release liner 162.Removal of the release liner 162 may expose the base layer 132 and theadhesive 136 for application of the dressing 124 to the tissue site 104.The release liner 162 may also provide stiffness to assist with, forexample, deployment of the dressing 124. The release liner 162 may be,for example, a casting paper, a film, or polyethylene. Further, therelease liner 162 may be a polyester material such as polyethyleneterephthalate (PET), or similar polar semi-crystalline polymer. The useof a polar semi-crystalline polymer for the release liner 162 maysubstantially preclude wrinkling or other deformation of the dressing124. For example, the polar semi-crystalline polymer may be highlyorientated and resistant to softening, swelling, or other deformationthat may occur when brought into contact with components of the dressing124, or when subjected to temperature or environmental variations, orsterilization. Further, a release agent may be disposed on a side of therelease liner 162 that is configured to contact the base layer 132. Forexample, the release agent may be a silicone coating and may have arelease factor suitable to facilitate removal of the release liner 162by hand and without damaging or deforming the dressing 124. In someembodiments, the release agent may be fluorosilicone. In otherembodiments, the release liner 162 may be uncoated or otherwise usedwithout a release agent.

Continuing with FIGS. 1-4B, the sealing member 140 may also be referredto as a dressing sealing member 140. The sealing member 140 may have aperiphery 164 and a central portion 168. The sealing member 140 mayadditionally include an aperture 170. The periphery 164 of the sealingmember 140 may be positioned proximate to the periphery 152 of the baselayer 132 such that the central portion 168 of the sealing member 140and the central portion 156 of the base layer 132 define an enclosure172. The adhesive 136 may be positioned at least between the periphery164 of the sealing member 140 and the periphery 152 of the base layer132. The sealing member 140 may cover the tissue site 104 and theinterface manifold 120 to provide a fluid seal and a sealed space 174between the tissue site 104 and the sealing member 140 of the dressing124. Further, the sealing member 140 may cover other tissue, such as aportion of the epidermis 106, surrounding the tissue site 104 to providethe fluid seal between the sealing member 140 and the tissue site 104.In some embodiments, a portion of the periphery 164 of the sealingmember 140 may extend beyond the periphery 152 of the base layer 132 andinto direct contact with tissue surrounding the tissue site 104. Inother embodiments, the periphery 164 of the sealing member 140, forexample, may be positioned in contact with tissue surrounding the tissuesite 104 to provide the sealed space 174 without the base layer 132.Thus, the adhesive 136 may also be positioned at least between theperiphery 164 of the sealing member 140 and tissue, such as theepidermis 106, surrounding the tissue site 104. The adhesive 136 may bedisposed on a surface of the sealing member 140 adapted to face thetissue site 104 and the base layer 132.

The sealing member 140 may be formed from any material that allows for afluid seal. A fluid seal may be a seal adequate to maintain reducedpressure at a desired site given the particular reduced pressure sourceor system involved. The sealing member 140 may comprise, for example,one or more of the following materials: hydrophilic polyurethane;cellulosics; hydrophilic polyamides; polyvinyl alcohol; polyvinylpyrrolidone; hydrophilic acrylics; hydrophilic silicone elastomers; anINSPIRE 2301 material from Expopack Advanced Coatings of Wrexham, UnitedKingdom having, for example, an MVTR (inverted cup technique) of 14400g/m²/24 hours and a thickness of about 30 microns; a thin, uncoatedpolymer drape; natural rubbers; polyisoprene; styrene butadiene rubber;chloroprene rubber; polybutadiene; nitrile rubber; butyl rubber;ethylene propylene rubber; ethylene propylene diene monomer;chlorosulfonated polyethylene; polysulfide rubber; polyurethane (PU);EVA film; co-polyester; silicones; a silicone drape; a 3M Tegaderm®drape; a polyurethane (PU) drape such as one available from AveryDennison Corporation of Pasadena, Calif.; a polyurethane (PU) film suchas Scapa Bioflex 130 polyurethane Film®; polyether block polyamidecopolymer (PEBAX), for example, from Arkema, France; Expopack 2327; orother appropriate material.

The sealing member 140 may be vapor permeable and liquid impermeable,thereby allowing vapor and inhibiting liquids from exiting the sealedspace 174 provided by the dressing 124. In some embodiments, the sealingmember 140 may be a flexible, breathable film, membrane, or sheet havinga high MVTR of, for example, at least about 300 g/m² per 24 hours. Inother embodiments, a low or no vapor transfer drape may be used. Thesealing member 140 may comprise a range of medically suitable filmshaving a thickness between about 15 microns (μm) to about 50 microns(μm).

The fluid management assembly 144 may be disposed in the enclosure 172.In some embodiments, the fluid management assembly 144 may include afirst dressing wicking layer 176, a second dressing wicking layer 180,and an absorbent layer 184. The absorbent layer 184 may also be referredto as a dressing absorbent 184. The absorbent layer 184 may bepositioned in fluid communication between the first dressing wickinglayer 176 and the second dressing wicking layer 180. The first dressingwicking layer 176 may have a grain structure adapted to wick fluid alonga surface of the first dressing wicking layer 176. Similarly, the seconddressing wicking layer 180 may have a grain structure adapted to wickfluid along a surface of the second dressing wicking layer 180. Forexample, the first dressing wicking layer 176 and the second dressingwicking layer 180 may wick or otherwise transport fluid in a lateraldirection along the surfaces of the first dressing wicking layer 176 andthe second dressing wicking layer 180, respectively. The surface of thefirst dressing wicking layer 176 may be normal relative to the thicknessof the first dressing wicking layer 176, and the surface of the seconddressing wicking layer 180 may be normal relative to the thickness ofthe second dressing wicking layer 180. The wicking of fluid along thefirst dressing wicking layer 176 and the second dressing wicking layer180 may enhance the distribution of the fluid over a surface area of theabsorbent layer 184, which may increase absorbent efficiency and resistfluid blockages. Fluid blockages may be caused by, for example, fluidpooling in a particular location in the absorbent layer 184 rather thanbeing distributed more uniformly across the absorbent layer 184. Thelaminate combination of the first dressing wicking layer 176, the seconddressing wicking layer 180, and the absorbent layer 184 may be adaptedas described above to maintain an open structure, resistant to blockage,capable of maintaining fluid communication with, for example, the tissuesite 104.

Referring to the embodiments of the fluid management assembly 144depicted in FIGS. 1, 2, 5, and 6 , a peripheral portion 186 of the firstdressing wicking layer 176 may be coupled to a peripheral portion 187 ofthe second dressing wicking layer 180 to define a wicking layerenclosure 188 between the first dressing wicking layer 176 and thesecond dressing wicking layer 180. In some embodiments, the wickinglayer enclosure 188 may surround or otherwise encapsulate the absorbentlayer 184 between the first dressing wicking layer 176 and the seconddressing wicking layer 180.

Referring to FIGS. 5 and 6 , in some embodiments, the fluid managementassembly 144 may include, without limitation, any number of wickinglayers and absorbent layers as desired for treating a particular tissuesite. For example, the absorbent layer 184 may be a plurality ofabsorbent layers 184 positioned in fluid communication between the firstdressing wicking layer 176 and the second dressing wicking layer 180.Further, as shown in FIG. 6 , in some embodiments, at least oneintermediate wicking layer 189 may be disposed in fluid communicationbetween the plurality of absorbent layers 184. Similar to the absorbentlayer 184, the plurality of absorbent layers 184 and the at least oneintermediate wicking layer 189 may be positioned within the wickinglayer enclosure 188. In some embodiments, the absorbent layer 184 may bedisposed between the sealing member 140 and the interface manifold 120,and the first dressing wicking layer 176 and the second dressing wickinglayer 180 may be omitted.

Continuing with FIGS. 5 and 6 , sides 184 a of the absorbent layers 184may remain in fluid communication with one another for enhancingefficiency. Similarly, sides 189 a of the at least one intermediatewicking layer 189 shown in FIG. 6 may remain in fluid communication withone another and with the sides 184 a of the absorbent layers 184.Further, including additional absorbent layers 184 may increase theabsorbent mass of the fluid management assembly 144 and generallyprovide greater fluid capacity. However, for a given absorbent mass,multiple light coat-weight absorbent layers 184 may be utilized ratherthan a single heavy coat-weight absorbent layer 184 to provide a greaterabsorbent surface area for further enhancing the absorbent efficiency.

In some embodiments, the absorbent layer 184 may be a hydrophilicmaterial adapted to absorb fluid from, for example, the tissue site 104.Materials suitable for the absorbent layer 184 may include, withoutlimitation, super absorbent polymers and similar absorbent materials;Luquafleece® material; TEXSUS FP2326; BASF 402C; Technical Absorbents2317, available from Technical Absorbents, Ltd. of Lincolnshire, UnitedKingdom; sodium polyacrylate super absorbers; cellulosics (carboxymethyl cellulose and salts such as sodium CMC); Gelok® 30040-76 S/S/S300 gsm absorbent; or alginates. Materials suitable for the firstdressing wicking layer 176 and the second dressing wicking layer 180 mayinclude, without limitation, any material having a grain structurecapable of wicking fluid as described herein, such as, for example,LIBELTEX TDL2, 80 gsm, or similar materials, which may be non-woven.

The fluid management assembly 144 may be manufactured as a pre-laminatedstructure, or supplied as individual layers of material that can bestacked upon one another as described above. Individual layers of thefluid management assembly 144 may be bonded or otherwise secured to oneanother without adversely affecting fluid management by, for example,utilizing a solvent or non-solvent adhesive, or by thermal welding.Further, the fluid management assembly 144 may be coupled to the border161 of the base layer 132 in any suitable manner, such as, for example,by a weld or an adhesive. The border 161, being free of the apertures160 as described above, may provide a flexible barrier between the fluidmanagement assembly 144 and the tissue site 104 for enhancing comfort.

The dressing 124 may be modified in various embodiments to suit aparticular application. In some embodiments, the absorbent layer 184 maybe omitted from the fluid management assembly 144, which may bebeneficial, but not required, for communicating fluid exterior to oraway from the dressing 124 and the tissue site 104 for offsite or remotestorage. In such an embodiment, the first dressing wicking layer 176 andthe second dressing wicking layer 180 may wick or draw fluid away fromthe tissue site 104 for transport to a location exterior to the dressing124. Further, the configuration of the first dressing wicking layer 176and the second dressing wicking layer 180 described herein maypreference fluid away from the tissue site 104 and prevent the fluidfrom returning to the tissue site 104 prior to removal of the fluid fromthe dressing 124, for example, by the application of reduced pressure.The wicking layer enclosure 188 may enhance this ability to preferencefluid away from the tissue site 104 and to prevent the fluid fromreturning to the tissue site 104.

The dressing 124 may be further modified in various embodiments that maybe suitable for some applications that communicate fluid from the tissuesite 104 exterior to the dressing 124. For example, in some embodiments,the first dressing wicking layer 176 or the second dressing wickinglayer 180 may be omitted along with the absorbent layer 184 and the baselayer 132. In such an embodiment, the dressing 124 may comprise thesealing member 140 and one of the first dressing wicking layer 176 orthe second dressing wicking layer 180 for disposing in the sealed space174 between the sealing member 140 and the tissue site 104. Further, insome embodiments, the fluid management assembly 144 may be omitted fromthe dressing 124, and a dressing manifold (not shown) may be positionedin the enclosure 172 in place of the fluid management assembly 144. Thedressing manifold may be configured as a layer and may be comprised ofany material suitable for removing fluids from a tissue site through aplurality of pores, pathways, or flow channels as described herein, suchas, without limitation, a foam, a woven material, a cast silicone, apolyurethane material, or any of the materials recited above for theinterface manifold 120. Further, in some embodiments, the dressing 124may be modified by omitting the base layer 132 and replacing the fluidmanagement assembly 144 with the above-described dressing manifold. Insuch an embodiment, the dressing 124 may comprise the sealing member 140and the dressing manifold for disposing in the sealed space 174 betweenthe sealing member 140 and the tissue site 104. Further, in someembodiments, the absorbent layer 184 may be omitted and replaced withthe dressing manifold such that the dressing manifold is positionedbetween the first dressing wicking layer 176 and the second dressingwicking layer 180.

Referring to FIGS. 1 and 2 , in some embodiments, the enclosure 172defined by the base layer 132 and the sealing member 140 may include anoptional anti-microbial layer 190. The addition of the anti-microbiallayer 190 may reduce the probability of excessive bacterial growthwithin the dressing 124 to permit the dressing 124 to remain in placefor an extended period. The anti-microbial layer 190 may be, forexample, an additional layer included as a part of the fluid managementassembly 144, or a coating of an anti-microbial agent disposed in anysuitable location within the dressing 124. The anti-microbial layer 190may be comprised of elemental silver or a similar compound, for example.In some embodiments, the anti-microbial agent may be formulated in anysuitable manner and associated with other components of the dressing124.

Referring to FIGS. 1, 2, and 7 , the conduit interface 148 may bepositioned proximate to the sealing member 140 and in fluidcommunication with the enclosure 172 of the dressing 124. For example,the conduit interface 148 may be in fluid communication with thedressing 124 through the aperture 170 in the sealing member 140. Theconduit interface 148 may provide reduced pressure from thereduced-pressure source 128 to the dressing 124. The conduit interface148 may also be adapted to be positioned in fluid communication with theoptional interface manifold 120. An optional liquid trap 192 may bepositioned in fluid communication between the dressing 124 and thereduced-pressure source 128. The liquid trap 192 may be any suitablecontainment device having a sealed internal volume capable of retainingliquid, such as condensate or other liquids.

The conduit interface 148 may comprise a medical-grade, soft polymer orother pliable material. As non-limiting examples, the conduit interface148 may be formed from polyurethane, polyethylene, polyvinyl chloride(PVC), fluorosilicone, or ethylene-propylene. In some illustrative,non-limiting embodiments, conduit interface 148 may be molded fromDEHP-free PVC. The conduit interface 148 may be formed in any suitablemanner such as by molding, casting, machining, or extruding. Further,the conduit interface 148 may be formed as an integral unit or asindividual components and may be coupled to the dressing 124 by, forexample, adhesive or welding.

In some embodiments, the conduit interface 148 may be formed of anabsorbent material having absorbent and evaporative properties. Theabsorbent material may be vapor permeable and liquid impermeable,thereby being configured to permit vapor to be absorbed into andevaporated from the material through permeation while inhibitingpermeation of liquids. The absorbent material may be, for example, ahydrophilic polymer such as a hydrophilic polyurethane. Although theterm hydrophilic polymer may be used in the illustrative embodimentsthat follow, any absorbent material having the properties describedherein may be suitable for use in the system 102. Further, the absorbentmaterial or hydrophilic polymer may be suitable for use in variouscomponents of the system 102 as described herein.

The use of such a hydrophilic polymer for the conduit interface 148 maypermit liquids in the conduit interface 148 to evaporate, or otherwisedissipate, during operation. For example, the hydrophilic polymer mayallow the liquid to permeate or pass through the conduit interface 148as vapor, in a gaseous phase, and evaporate into the atmosphere externalto the conduit interface 148. Such liquids may be, for example,condensate or other liquids. Condensate may form, for example, as aresult of a decrease in temperature within the conduit interface 148, orother components of the system 102, relative to the temperature at thetissue site 104. Removal or dissipation of liquids from the conduitinterface 148 may increase visual appeal and prevent odor. Further, suchremoval of liquids may also increase efficiency and reliability byreducing blockages and other interference with the components of thesystem 102.

Similar to the conduit interface 148, the liquid trap 192, and othercomponents of the system 102, may also be formed of an absorbentmaterial or a hydrophilic polymer. The absorptive and evaporativeproperties of the hydrophilic polymer may also facilitate removal anddissipation of liquids residing in the liquid trap 192, and othercomponents of the system 102, by evaporation. Such evaporation may leavebehind a substantially solid or gel-like waste. The substantially solidor gel-like waste may be cheaper to dispose than liquids, providing acost savings for operation of the system 102. The hydrophilic polymermay be used for other components in the system 102 where the managementof liquids is beneficial.

In some embodiments, the absorbent material or hydrophilic polymer mayhave an absorbent capacity in a saturated state that is substantiallyequivalent to the mass of the hydrophilic polymer in an unsaturatedstate. The hydrophilic polymer may be fully saturated with vapor in thesaturated state and substantially free of vapor in the unsaturatedstate. In both the saturated state and the unsaturated state, thehydrophilic polymer may retain substantially the same physical,mechanical, and structural properties. For example, the hydrophilicpolymer may have a hardness in the unsaturated state that issubstantially the same as a hardness of the hydrophilic polymer in thesaturated state. The hydrophilic polymer and the components of thesystem 102 incorporating the hydrophilic polymer may also have a sizethat is substantially the same in both the unsaturated state and thesaturated state. Further, the hydrophilic polymer may remain dry, coolto the touch, and pneumatically sealed in the saturated state and theunsaturated state. The hydrophilic polymer may also remain substantiallythe same color in the saturated state and the unsaturated state. In thismanner, this hydrophilic polymer may retain sufficient strength andother physical properties to remain suitable for use in the system 102.An example of such a hydrophilic polymer is offered under the trade nameTechophilic HP-93A-100, available from The Lubrizol Corporation ofWickliffe, Ohio, United States. Techophilic HP-93A-100 is an absorbenthydrophilic thermoplastic polyurethane capable of absorbing 100% of theunsaturated mass of the polyurethane in water and having a durometer orShore Hardness of about 83 Shore A.

The conduit interface 148 may carry an odor filter 194 adapted tosubstantially preclude the passage of odors from the tissue site 104 outof the sealed space 174. Further, the conduit interface 148 may carry aprimary hydrophobic filter 195 adapted to substantially preclude thepassage of liquids through the primary hydrophobic filter 195. The odorfilter 194 and the primary hydrophobic filter 195 may be disposed in theconduit interface 148 or other suitable location such that fluidcommunication between the reduced-pressure source 128, or optionaltherapy unit 130, and the dressing 124 is provided through the odorfilter 194 and the primary hydrophobic filter 195. In some embodiments,the odor filter 194 and the primary hydrophobic filter 195 may besecured within the conduit interface 148 in any suitable manner, such asby adhesive or welding. In other embodiments, the odor filter 194 or theprimary hydrophobic filter 195 may be omitted, or positioned proximateto any exit location in the system 102 or the dressing 124 that is influid communication with the atmosphere, the reduced-pressure source128, or the optional therapy unit 130.

The odor filter 194 may be comprised of a carbon material in the form ofa layer or particulate. For example, the odor filter 194 may comprise awoven carbon cloth filter such as those manufactured by ChemvironCarbon, Ltd. of Lancashire, United Kingdom. The primary hydrophobicfilter 195 may be comprised of a material that is liquid impermeable andvapor permeable. For example, the primary hydrophobic filter 195 maycomprise a material manufactured under the designation MMT-314 by W.L.Gore & Associates, Inc. of Newark, Del., United States, or similarmaterials. The primary hydrophobic filter 195 may be provided in theform of a membrane or layer.

Continuing with FIGS. 1, 2, and 7 , the reduced-pressure source 128 mayprovide reduced pressure to the dressing 124 and the sealed space 174.The reduced-pressure source 128 may be any suitable device for providingreduced pressure, such as, for example, a vacuum pump, wall suction,hand pump, manual pump, or other source. In some embodiments, thereduced-pressure source 128 may be a component of the therapy unit 130.The therapy unit 130 may include control circuitry and sensors, such asa pressure sensor, that may be configured to monitor reduced pressure atthe tissue site 104. The therapy unit 130 may also be configured tocontrol the amount of reduced pressure from the reduced-pressure source128 being applied to the tissue site 104 according to a user input and areduced-pressure feedback signal received from the tissue site 104. Insome embodiments, the reduced pressure source 128 (such as a manualpump, hand pump, or the like) may comprise a container or may be fluidlyconnected to a container that receives fluid collected from the tissuesite 104. Thus, when the reduced pressure source 128 generates reducedpressure, fluid may be communicated from the tissue site, through thedressing, through the bridge, and received and stored in the containerof the reduced pressure source 128 or fluidly connected to the reducedpressure source 128.

As used herein, “reduced pressure” may refer to a pressure less than theambient pressure at a tissue site being subjected to treatment. In someembodiments, the reduced pressure may be less than the atmosphericpressure. Further, in some embodiments, the reduced pressure may also beless than a hydrostatic pressure at a tissue site. Unless otherwiseindicated, values of pressure stated herein are gauge pressures. Whilethe amount and nature of reduced pressure applied to a tissue site mayvary according to the application, in some embodiments, the reducedpressure may be between −5 mm Hg and −500 mm Hg. In some embodiments,the reduced pressure may be between −100 mm Hg and −200 mm Hg.

The reduced pressure delivered may be, for example, constant, varied,patterned, or random. Further, the reduced pressure may be deliveredcontinuously or intermittently. Although the terms “vacuum” and“negative pressure” may be used to describe the pressure applied to atissue site, the actual pressure applied to the tissue site may be morethan the pressure normally associated with a complete vacuum. Consistentwith the use herein, an increase in reduced pressure or vacuum pressuremay refer to a relative reduction in absolute pressure. Further, anincrease in reduced pressure may correspond to a reduction in pressure(more negative relative to ambient pressure), and a decrease in reducedpressure may correspond to an increase in pressure (less negativerelative to ambient pressure).

Referring to FIGS. 1 and 7 , a conduit 196 having an internal lumen 197may be coupled in fluid communication between the reduced-pressuresource 128 and the dressing 124. The internal lumen 197 may have aninternal diameter between about 0.5 millimeters to about 3.0millimeters. In some embodiments, the internal diameter of the internallumen 197 may be between about 1 millimeter to about 2 millimeters. Theconduit interface 148 may be coupled in fluid communication with thedressing 124 and adapted to connect between the conduit 196 and thedressing 124 for providing fluid communication with the reduced-pressuresource 128. The conduit interface 148 may be fluidly coupled to theconduit 196 in any suitable manner, such as, for example, by anadhesive, solvent or non-solvent bonding, welding, or interference fit.The aperture 170 in the sealing member 140 may provide fluidcommunication between the dressing 124 and the conduit interface 148.For example, the conduit interface 148 may be in fluid communicationwith the enclosure 172 or the sealed space 174 through the aperture 170in the sealing member 140. In some embodiments, the conduit 196 may beinserted into the dressing 124 through the aperture 170 in the sealingmember 140 to provide fluid communication with the reduced-pressuresource 128 without use of the conduit interface 148. Thereduced-pressure source 128 may also be directly coupled in fluidcommunication with the dressing 124 or the sealing member 140 withoutuse of the conduit 196. In some embodiments, the conduit 196 may be, forexample, a flexible polymer tube. A distal end of the conduit 196 mayinclude a coupling 198 for attachment to the reduced-pressure source128.

The conduit 196 may have a secondary hydrophobic filter 199 disposed inthe internal lumen 197 such that fluid communication between thereduced-pressure source 128 and the dressing 124 is provided through thesecondary hydrophobic filter 199. The secondary hydrophobic filter 199may be, for example, a porous, sintered polymer cylinder sized to fitthe dimensions of the internal lumen 197 to substantially precludeliquid from bypassing the cylinder. The secondary hydrophobic filter 199may also be treated with an absorbent material adapted to swell whenbrought into contact with liquid to block the flow of the liquid. Thesecondary hydrophobic filter 199 may be positioned at any locationwithin the internal lumen 197. However, positioning the secondaryhydrophobic filter 199 within the internal lumen 197 closer toward thereduced-pressure source 128, rather than the dressing 124, may allow auser to detect the presence of liquid in the internal lumen 197.

In some embodiments, the conduit 196 and the coupling 198 may be formedof an absorbent material or a hydrophilic polymer as described above forthe conduit interface 148. In this manner, the conduit 196 and thecoupling 198 may permit liquids in the conduit 196 and the coupling 198to evaporate, or otherwise dissipate, as described above for the conduitinterface 148. The conduit 196 and the coupling 198 may be, for example,molded from the hydrophilic polymer separately, as individualcomponents, or together as an integral component. Further, a wall of theconduit 196 defining the internal lumen 197 may be extruded from thehydrophilic polymer. The conduit 196 may be less than about 1 meter inlength, but may have any length to suit a particular application.

Referring to FIG. 8 , another embodiment of a fluid management assembly244 suitable for use with the dressing 124 and the system 102 is shown.The fluid management assembly 244 may include a first dressing wickinglayer 276, a second dressing wicking layer 280, and an absorbent layer284 comprised of substantially the same materials and properties asthose described above in connection with the fluid management assembly144. Thus, the first dressing wicking layer 276, the second dressingwicking layer 280, and the absorbent layer 284 may be analogous to thefirst dressing wicking layer 176, the second dressing wicking layer 180,and the absorbent layer 184, respectively.

In the fluid management assembly 244, the second dressing wicking layer280 may have a peripheral portion 287. The second dressing wicking layer280 and the peripheral portion 287 of the second dressing wicking layer280 may be positioned in contact with the sealing member 140. Theabsorbent layer 284 may have a peripheral portion 285 extending beyondthe peripheral portion 287 of the second dressing wicking layer 280. Theabsorbent layer 284 may be positioned adjacent to or proximate to thesecond dressing wicking layer 280 such that the peripheral portion 285of the absorbent layer 284 is in contact with the sealing member 140surrounding the peripheral portion 287 of the second dressing wickinglayer 280. Similarly, the first dressing wicking layer 276 may have aperipheral portion 286 extending beyond the peripheral portion 285 ofthe absorbent layer 284. The first dressing wicking layer 276 may bepositioned adjacent to or proximate to the absorbent layer 284 such thatthe peripheral portion 286 of the first dressing wicking layer 276 is incontact with the sealing member 140 surrounding the peripheral portion285 of the absorbent layer 284. Further, the first dressing wickinglayer 276 may be positioned adjacent to or proximate to the base layer132. Thus, at least the peripheral portion 287, the peripheral portion285, and the peripheral portion 286 may be coupled to the sealing member140, such as, for example, by an adhesive coating disposed on a surfaceof the sealing member 140 facing the base layer 132. The adhesivecoating may be analogous to the adhesive 136 that may be applied acrossthe surface of the sealing member 140 facing the base layer 132. Thesecond dressing wicking layer 280, the absorbent layer 284, and thefirst dressing wicking layer 276 may respectively have increasingsurface areas to enhance contact with the adhesive coating describedabove. In other embodiments, the fluid management assembly 244 mayinclude any number of absorbent layers and wicking layers for treating aparticular tissue site.

In operation, according to some illustrative embodiments, the interfacemanifold 120 may be disposed against or proximate to the tissue site104. The dressing 124 may be applied over or covering the interfacemanifold 120 and the tissue site 104 to form the sealed space 174. Forexample, the base layer 132 may be applied covering the interfacemanifold 120 and tissue surrounding the tissue site 104. The materialsdescribed above for the base layer 132 may have a tackiness that mayhold the dressing 124 initially in position. The tackiness may be suchthat if an adjustment is desired, the dressing 124 may be removed andreapplied. Once the dressing 124 is in the desired position, a force maybe applied, such as hand pressure, on a side of the sealing member 140facing outward or opposite the tissue site 104. The force applied to thesealing member 140 may cause at least some portion of the adhesive 136to penetrate or extend through the plurality of apertures 160 and intocontact with tissue surrounding the tissue site 104, such as theepidermis 106, to releasably adhere the dressing 124 about the tissuesite 104. In this manner, the configuration of the dressing 124described above may provide an effective and reliable seal againstchallenging anatomical surfaces, such as an elbow or heal, at and aroundthe tissue site 104. Further, the dressing 124 may permit re-applicationor re-positioning to, for example, correct air leaks caused by creasesand other discontinuities in the dressing 124 and the tissue site 104.The ability to rectify leaks may increase the reliability of the therapyand reduce power consumption.

As the dressing 124 comes into contact with fluid from the tissue site104, the fluid may move through the apertures 160 toward the fluidmanagement assembly 144, 244. The fluid management assembly 144, 244 maywick or otherwise move the fluid away from the tissue site 104, andthrough the interface manifold 120, if equipped. As described above, theinterface manifold 120 may be adapted to communicate fluid from thetissue site 104 rather than store the fluid. Thus, the fluid managementassembly 144, 244 may be adapted to wick, pull, draw, or otherwiseattract fluid from the tissue site 104 through the interface manifold120. In the fluid management assembly 144, 244, the fluid may initiallycome into contact with the first dressing wicking layer 176, 276. Thefirst dressing wicking layer 176, 276 may distribute the fluid laterallyalong the surface of the first dressing wicking layer 176, 276 forabsorption or removal from the dressing 124. Similarly, fluid may comeinto contact with the second dressing wicking layer 180, 280 and may bedistributed laterally along the surface of the second dressing wickinglayer 180, 280 for absorption or removal from the dressing 124.

Referring to FIGS. 9-11 , in some embodiments, a bridge assembly 310 mayextend away from the tissue site 104 and the dressing 124 to define afluid passageway between the tissue site 104 and the reduced-pressuresource 128. For example, the bridge assembly 310 may be coupled in fluidcommunication between the dressing 124 and the reduced-pressure source128. However, other applications for the bridge assembly 310 arepossible. In some embodiments, the bridge assembly 310 may include astorage bridge 320, a sealing apparatus 330, and the conduit interface148. It should be understood, that while dressing 124 is described withreference to FIGS. 9-11 , dressings 324 or dressings 424, discussedherein, may additionally or alternatively be used with reference toFIGS. 9-11 .

The storage bridge 320 may include a receiving end 334 separated orspaced apart from a transmitting end 338 by a length 340. The receivingend 334 may have a receiving end aperture 342, and the transmitting end338 may have a transmitting end aperture 346. The receiving end 334 andthe receiving end aperture 342 may be in fluid communication with thetransmitting end 338 and the transmitting end aperture 346 through thelength 340 of the storage bridge 320.

The conduit interface 148 may be adapted to be fluidly coupled to thereceiving end 334 of the storage bridge 320 through, for example, thereceiving end aperture 342. Thus, the conduit interface 148 may be influid communication with the transmitting end 338 through the length 340of the storage bridge 320. The sealing apparatus 330 may be positionedabout the transmitting end aperture 346 and between the transmitting end338 and the dressing 124 for coupling the transmitting end 338 to thedressing 124 and in fluid communication with the dressing 124 throughthe transmitting end aperture 346. Thus, the conduit interface 148 maybe positioned in fluid communication with the dressing 124 through thestorage bridge 320. The sealing apparatus 330 may be any suitable devicefor making the connections described above, such as, without limitation,an adhesive ring or weld.

In some embodiments, the storage bridge 320 may include a bridgeenvelope 350, a bridge absorbent 354, and a bridge sealing member 358.The bridge envelope 350 may extend along the length 340 of the storagebridge 320. Further, the bridge envelope 350 may define an internalvolume 360. The bridge absorbent 354 may be disposed within the internalvolume 360 of the bridge envelope 350. In some embodiments, the bridgeabsorbent 354 may have a volume 362, in an unsaturated state, which isless than the internal volume 360 of the bridge envelope 350. In someembodiments, the bridge absorbent 354 may have a volume 362, in anunsaturated state, which is at least 5 percent less than the internalvolume 360 of the bridge envelope 350. In some embodiments, the bridgeabsorbent 354 may have a volume 362, in an unsaturated state, which isat least 10 percent less than the internal volume 360 of the bridgeenvelope 350. In some embodiments, the bridge absorbent 354 may have avolume 362, in an unsaturated state, which is between 20 percent toabout 90 percent of the internal volume 360 of the bridge envelope 350.In some embodiments, a cross-sectional area 364 of the bridge absorbent354 may be less than a cross-sectional area 366 of the bridge envelope350. The bridge absorbent 354 having a volume 362 or cross-sectionalarea 364 less than the internal volume 360 or cross-sectional area 366of the bridge envelope 350 may allow for free movement of fluids anddistribution of pressure around the bridge absorbent 354 when positionedwithin the internal volume 360 of the bridge envelope 350. In someembodiments, the bridge envelope 350 may entirely surround the bridgeabsorbent 354. Further, in some embodiments, the bridge envelope 350 mayencapsulate the bridge absorbent 354. Further, in some embodiments, thebridge absorbent 354 may be moveable, expandable, or swellable withinthe internal volume 360 of the bridge envelope 350. For example, thebridge absorbent 354 may be configured to move, expand, or swell whenthe bridge absorbent 354 becomes fully or partially saturated with aliquid.

Further, the bridge envelope 350 may include an internal surface 368 andthe bridge absorbent 354 may include an external surface 370. In someembodiments, at least a portion of the external surface 370 of thebridge absorbent 354 may be spaced apart or separated from the internalsurface 368 of the bridge envelope 350. Further, in some embodiments,the entire external surface 370 of the bridge absorbent 354 may beseparated or spaced apart from the internal surface 368 of the bridgeenvelope 350. Such a separation or space between the external surface370 of the bridge absorbent 354 and the internal surface 368 of thebridge envelope 350 may occur, for example, as a result of fluidspositioned between the external surface 370 and the internal surface 368during operation.

In some embodiments, the bridge envelope 350 may include a fluidacquisition surface 372 and a fluid distribution surface 374. The fluiddistribution surface 374 may be positioned opposite the fluidacquisition surface 372. The fluid distribution surface 374 may face theinternal volume 360 of the bridge envelope 350 and the bridge absorbent354. In some embodiments, at least a portion of the bridge absorbent 354may be spaced apart from the fluid distribution surface 374 of thebridge envelope 350. In some embodiments, the fluid distribution surface374 may include a plurality of longitudinal fibers 391 orientedsubstantially in a longitudinal direction along the length 340 of thestorage bridge 320. Further, in some embodiments, the fluid acquisitionsurface 372 may include a plurality of vertical fibers 393 orientedsubstantially normal relative to the longitudinal fibers 391.

In some embodiments, the bridge envelope 350 may include a first bridgewicking layer 380 and a second bridge wicking layer 382. The firstbridge wicking layer 380 and the second bridge wicking layer 382 mayeach extend along the length 340 of the storage bridge 320, and may bedisposed within an internal passageway 384 that may be defined by thebridge sealing member 358. A periphery or edge of the first bridgewicking layer 380 may be coupled to a periphery or edge of the secondbridge wicking layer 382 in any suitable manner, such as, for example,by a weld 386, to define the internal volume 360 of the bridge envelope350. The bridge absorbent 354 may be positioned between the first bridgewicking layer 380 and the second bridge wicking layer 382. The firstbridge wicking layer 380 and the second bridge wicking layer 382 mayeach include the fluid acquisition surface 372 and the fluiddistribution surface 374. The fluid distribution surface 374 may bepositioned on an opposite side of the first bridge wicking layer 380 andthe second bridge wicking layer 382 from the fluid acquisition surface372. Further, the fluid distribution surface 374 of the first bridgewicking layer 380 and the second bridge wicking layer 382 may face thebridge absorbent 354. In some embodiments, at least a portion of thebridge absorbent 354 may be spaced apart or separated from the fluiddistribution surface 374 of the first bridge wicking layer 380 and thesecond bridge wicking layer 382.

In some embodiments, the bridge envelope 350 may comprise a non-wovenmaterial or structure such as, without limitation, a polyester,co-polyester, polyolefin, cellulosic fiber, and combinations or blendsof the foregoing materials. In some embodiments, the bridge envelope 350may comprise LIBELTEX TDL4 or LIBELTEX TDL2, or any of the materialsrecited above for the first dressing wicking layer 176 and the seconddressing wicking layer 180. Further, in some embodiments, the bridgeenvelope 350 may comprise laminations with fiber or foam structures. Thefirst bridge wicking layer 380 and the second bridge wicking layer 382may each be comprised of the same materials recited above for the bridgeenvelope 350. In some embodiments, the bridge absorbent 354 may includea super-absorbent polymer or similar absorbent material, such as,without limitation, TEXSUS FP2325, or Gelok® 30040-76 S/S/S 300 gsmabsorbent. Further, in some embodiments, the bridge absorbent 354 maycomprise any of the materials recited above for the dressing absorbent184.

The bridge sealing member 358 may encapsulate the bridge envelope 350,and may define the internal passageway 384. The internal passageway 384may be in fluid communication between the receiving end 334 and thetransmitting end 338 of the storage bridge 320. In some embodiments, thebridge sealing member 358 may entirely surround the bridge envelope 350.In some embodiments, the bridge envelope 350 may be disposed within theinternal passageway 384 defined by the bridge sealing member 358. Insome embodiments, the bridge sealing member 358 may sealingly enclosethe bridge envelope 350 between the receiving end 334 and thetransmitting end 338 of the storage bridge 320.

The bridge sealing member 358 may be comprised of similar materialsdescribed above for the dressing sealing member 140. For example, insome embodiments, the bridge sealing member 358 may comprise asubstantially liquid impermeable film. Further, in some embodiments, thebridge sealing member 358 may comprise a vapor permeable film. Further,in some embodiments, the bridge sealing member 358 may comprise abreathable film. Additional examples of materials suitable for thebridge sealing member 358 may include, without limitation, apolyurethane drape or film such as Scapa Bioflex 130 polyurethane Film®;films formed from polymers, such as polyester and co-polyester;polyamide; polyamide/block polyether; acrylics; vinyl esters; polyvinylalcohol copolymers; films with and without adhesive; and high MoistureVapor Transfer Rate (MVTR) films, such as, for example, an INSPIRE 2305polyurethane drape. High MVTR films may provide for evaporation ofcondensate, which may occur around the entire exterior surface of thestorage bridge 320. In this manner, capacity, fluid handling, andevaporative properties of the storage bridge 320 may be enhanced orimproved due at least to increased surface area and air movementprovided around all sides and portions of the exterior surface of thestorage bridge 320.

In some embodiments, the bridge sealing member 358 may include a firstsealing layer 388 and a second sealing layer 390. A first periphery oredge of the first sealing layer 388 may be coupled to a second peripheryor edge of the second sealing layer 390 around the bridge envelope 350in any suitable manner, such as, for example, by a weld 392 for formingthe bridge sealing member 358 and encapsulating the bridge envelope 350therein. In other embodiments, the bridge sealing member 358 may beformed from a single layer of material.

The bridge assembly 310 may include features to indicate a level offluid retained in the storage bridge 320. For example, the storagebridge 320 may include a fluid capacity indicator 394 or a plurality offluid capacity indicators 394 positioned along the length 340 of thestorage bridge 320. In some embodiments, the fluid capacity indicators394 may be positioned sequentially along the length 340 of the storagebridge 320 to indicate an amount of fluid present or fluid capacityremaining in the storage bridge 320. The fluid capacity indicators 394may each identify a fraction or percentage of the total fluid capacityof the storage bridge 320. Further, in some embodiments, a liquidchanging dye (not shown) may be positioned within the internalpassageway 384 defined by the bridge sealing member 358 in any suitablemanner, such as, for example, as a coating, layer, or particulate. Theliquid changing dye may also indicate a level of fluid retained in thestorage bridge 320. Materials suitable for use as the liquid changingdye may include, without limitation, water soluble or swellablepolymers, such as polyvinyl alcohol and copolymers; acrylics;polyurethanes; and soluble salts, such as sodium, potassium, and sodiumacrylate. Water soluble dyes, such as, for example, indigo carmine orfast green FCF, may be mixed into the water soluble polymers set forthabove. Such a compound may swell or dissolve when exposed to fluid,which may release the dye, indicating the fluid level in the storagebridge 320.

In operation, the reduced-pressure source 128 may be fluidly coupled tothe receiving end 334 of the storage bridge 320. For example, theconduit interface 148 may be fluidly coupled to the receiving end 334,and the conduit 196 may be fluidly coupled between the conduit interface148 and the reduced-pressure source 128 analogous to the previouslydescribed embodiments. The transmitting end 338 of the storage bridge320 may be fluidly coupled to the dressing 124 as described above. Thereduced-pressure source 128 may be activated to provide reduced pressureto the dressing 124 through the storage bridge 320, which may draw,wick, or pull fluids from the tissue site 104 and the dressing 124 intothe storage bridge 320.

The structure of the storage bridge 320 may be configured to be morehydrophilic or absorbent than the dressing 124. For example, in somepreviously described embodiments, the dressing 124 may be configuredwithout an absorbent while the storage bridge 320 is configured with thebridge absorbent 354. In other embodiments, the dressing 124 may includecomponents that possess some absorbency, but less absorbency than thestorage bridge 320. Accordingly, the system 102 may be configured withan absorbent gradient that increases in absorbency or hydrophilicitywith increasing distance away from the tissue site 104, such as, forexample, from the dressing 124 toward the reduced-pressure source 128.Therefore, fluids may be drawn from the tissue site 104 into the storagebridge 320 by the application of the reduced pressure and by operationof attractive forces that may be exerted on the fluid by the absorbentgradient.

As fluid enters the storage bridge 320, the fluid may first contactportions of the bridge absorbent 354 near the transmitting end 338 ofthe storage bridge 320, which may become saturated with the fluid orblocked. Such fluid saturation or blockage near the transmitting end 338of the storage bridge 320 may force the fluid to move along the length340 of the storage bridge 320, between the external surface 370 of thestorage bridge 320 and the internal surface 368 of the bridge envelope350, toward the receiving end 334 of the storage bridge 320 forabsorption. The internal surface 368 of the bridge envelope 350 may alsobe the fluid distribution surface 374 of the bridge envelope 350, whichmay enhance the movement and distribution of the fluid within theinternal volume 360 of the bridge envelope 350 and the bridge absorbent354. The fluid may also wick or travel along the fluid acquisitionsurface 372 along the length 340 of the storage bridge 320 and passthrough or permeate the bridge envelope 350 to the fluid distributionsurface 374 for distribution to the bridge absorbent 354. The fluid maycontinue to travel in this manner along the length 340 of the storagebridge 320 from the transmitting end 338 to the receiving end 334 untilthe storage bridge 320 reaches full fluid capacity. Portions of thestorage bridge 320 that become saturated or blocked with fluid may swelland serve as an indication of the level of fluid contained in thestorage bridge 320. The fluid capacity indicator 394 and the liquidchanging dye may also provide an indication of fluid capacity asdescribed above.

Referring to FIG. 12 , a graphical plot of pressure in the dressing 124versus fluid volume is shown as a result of performance testing. In thetesting, the storage bridge 320 was assembled with the dressing 124according to this disclosure. The storage bridge 320 was held in avertical position, and a reduced pressure of 125 mmHg was applied to thedressing 124 through the storage bridge 320. Pressure measurements weretaken in the dressing 124 at an edge Y and a center X of the dressing124, shown in FIG. 9 , during delivery of saline fluid to the dressing124 at a rate of 0.83 cc per hour. As shown in FIG. 12 , the measuredpressure remained stable between about 115 mmHg to about 125 mmHg,illustrating that no significant drop in reduced pressure occurred inthe system 102 or though the storage bridge 320 during the addition ofthe saline in the testing.

Among other benefits described above, the storage bridge 320 may reducepower consumption, leakage, and other challenges that may be associatedwith fluid head pressure caused by a static column of fluid that canreside in a conventional tube or similar structure providing fluidcommunication between a dressing and a reduced-pressure source. Further,a mass of fluid removed from a tissue site may be moved away from thesurface of the tissue site. The storage bridge 320 may also provide alow-profile and conformable solution for providing fluid communicationwith a tissue site, which may enhance patient comfort.

Referring to the drawings, FIG. 13 depicts an illustrative embodiment ofa system 302 for treating a tissue site 104 of a patient. The tissuesite 104 may extend through or otherwise involve an epidermis 106, adermis 108, and a subcutaneous tissue 110. The tissue site 104 may be asub-surface tissue site as depicted in FIG. 13 that may extend below thesurface of the epidermis 106. Further, the tissue site 104 may be asurface tissue site (not shown) that may predominantly reside on thesurface of the epidermis 106, such as, for example, an incision. Thesystem 302 may provide therapy to, for example, the epidermis 106, thedermis 108, and the subcutaneous tissue 110, regardless of thepositioning of the system 302 or the type of tissue site. The system 302may be used to treat wound and shallow wounds on a patient such asvenous leg ulcers (VLUs). The system may also be attached to a patientover or near a wound and compressed against tissue at or near the woundusing bandages and/or compression garments (such as a compressiongarment with a hydrophobic coating). A compression garment (such as acompression garment with a hydrophobic coating) may prevent evaporatedfluid from pooling in the dressing of the system 302, reduce thelikelihood of infection, and the negative impact on patient wellbeing asa result of odor. In some embodiments, a compression garment may includean activated charcoal component to mitigate odor. The activated charcoalcomponent may increase evaporation rates from the dressing of the system302 as fluid molecules will be drawn to the coated compression garment.The system 302 under compression against tissue may provide a lowprofile on a patient. The system 302 may also be used without limitationat other tissue sites.

The tissue site 104 may be the bodily tissue of any human, animal, orother organism, including bone tissue, adipose tissue, muscle tissue,dermal tissue, vascular tissue, connective tissue, cartilage, tendons,ligaments, or any other tissue. Treatment of the tissue site 104 mayinclude the removal of fluids, such as exudate or ascites.

Continuing with FIG. 13 , the system 302 may include an optional tissueinterface, such as an interface manifold 120. Further, the system 302may include a dressing 324 and a reduced-pressure source 128. Thereduced-pressure source 128 may be a component of an optional therapyunit 130. In some embodiments, the reduced-pressure source 128 and thetherapy unit 130 may be separate components. Further, in someembodiments, the interface manifold 120 may be omitted for differenttypes of tissue sites or different types of therapy, such as, forexample, epithelialization. If equipped, the interface manifold 120 maybe adapted to be positioned proximate to or adjacent to the tissue site104, such as, for example, by cutting or otherwise shaping the interfacemanifold 120 in any suitable manner to fit the tissue site 104. Asdescribed below, the interface manifold 120 may be adapted to bepositioned in fluid communication with the tissue site 104 to distributereduced pressure to the tissue site 104. In some embodiments, theinterface manifold 120 may be positioned in direct contact with thetissue site 104.

The tissue interface or the interface manifold 120 may be formed fromany manifold material or flexible bolster material that provides avacuum space, or treatment space, such as, for example, a porous andpermeable foam or foam-like material, a member formed with pathways, agraft, a non-adherent material, a non-adherent copolymer mesh, or agauze. In some embodiments, the interface manifold 120 may be areticulated, open-cell polyurethane or polyether foam that may be fluidpermeable while under a reduced pressure. One such foam material is VAC®GranuFoam® material available from Kinetic Concepts, Inc. (KCI) of SanAntonio, Tex. Further, in some embodiments, any material or combinationof materials may be used as a manifold material for the interfacemanifold 120 provided that the manifold material is operable todistribute or collect fluid. For example, herein the term manifold mayrefer to a substance or structure configured for delivering fluids to orremoving fluids from a tissue site through a plurality of pores,pathways, or flow channels. The plurality of pores, pathways, or flowchannels may be interconnected to improve the distribution of fluidsprovided to and removed from an area around the manifold. Examples ofmanifolds may include, without limitation, devices that have structuralelements arranged to form flow channels, cellular foam, such asopen-cell foam, porous tissue collections, and liquids, gels, and foamsthat include or cure to include flow channels.

In some embodiments, a material with a higher or lower density thanGranuFoam® material may be desirable for the interface manifold 120depending on the application. Among the many possible materials, thefollowing may be used without limitation: GranuFoam® material; Foamex®technical foam (www.foamex.com); a molded bed of nails structure; apatterned grid material, such as those manufactured by Sercol IndustrialFabrics; 3D textiles, such as those manufactured by Baltex of Derby,U.K.; a gauze; a flexible channel-containing member; or a graft.Further, in some embodiments, ionic silver may be added to the interfacemanifold 120 by, for example, a micro bonding process. Other substances,such as anti-microbial agents, may be added to the interface manifold120 as well.

In some embodiments, the interface manifold 120 may comprise a porous,hydrophobic material. The hydrophobic characteristics of the interfacemanifold 120 may prevent the interface manifold 120 from directlyabsorbing fluid, such as exudate, from the tissue site 104, but allowthe fluid to pass through.

In some embodiments, the dressing 324 may include a base layer 132, anadhesive 136, a sealing member 140, a fluid management assembly 344, anda conduit interface 148. Components of the dressing 324 may be added orremoved to suit a particular application. In some embodiments, thedressing 324 may be adapted to provide reduced pressure from thereduced-pressure source 128 to the interface manifold 120, and toextract fluid from the tissue site 104 through the interface manifold120.

Referring to FIGS. 13-16B, the base layer 132 may have a periphery 152surrounding a central portion 156, and a plurality of apertures 160disposed through the periphery 152 and the central portion 156. The baselayer 132 may also have corners 158 and edges 159. The corners 158 andthe edges 159 may be part of the periphery 152. One of the edges 159 maymeet another of the edges 159 to define one of the corners 158. Further,the base layer 132 may have a border 161 substantially surrounding thecentral portion 156 and positioned between the central portion 156 andthe periphery 152. In some embodiments, the border 161 may be free ofthe apertures 160. In some embodiments, the base layer 132 may beadapted to cover the interface manifold 120 and tissue surrounding thetissue site 104 such that the central portion 156 of the base layer 132is positioned adjacent to or proximate to the interface manifold 120,and the periphery 152 of the base layer 132 is positioned adjacent to orproximate to tissue surrounding the tissue site 104. In suchembodiments, the periphery 152 of the base layer 132 may surround theinterface manifold 120. Further, the apertures 160 in the base layer 132may be in fluid communication with the interface manifold 120 and tissuesurrounding the tissue site 104.

The apertures 160 in the base layer 132 may have any shape, such as, forexample, circles, squares, stars, ovals, polygons, slits, complexcurves, rectilinear shapes, triangles, or other shapes. The apertures160 may be formed by cutting, by application of local RF energy, orother suitable techniques for forming an opening. Each of the apertures160 of the plurality of apertures 160 may be substantially circular inshape, having a diameter and an area. The area of the apertures 160described in the illustrative embodiments herein may be substantiallysimilar to the area in other embodiments for the apertures 160 that mayhave non-circular shapes. Further, the area of each of the apertures 160may be substantially the same, or each of the areas may vary, forexample, based on the position of the aperture 160 in the base layer132. For example, the area of the apertures 160 in the periphery 152 ofthe base layer 132 may be larger than the area of the apertures 160 inthe central portion 156 of the base layer 132. The apertures 160 mayhave a uniform pattern or may be randomly distributed on the base layer132. The size and configuration of the apertures 160 may be designed tocontrol the adherence of the dressing 124 to the epidermis 106 asdescribed herein.

In some embodiments, the apertures 160 positioned in the periphery 152may be apertures 160 a, the apertures 160 positioned at the corners 158of the periphery 152 may be apertures 160 b, and the apertures 160positioned in the central portion 156 may be apertures 160 c. In someembodiments, the apertures 160 a may have an area greater than theapertures 160 b. Further, in some embodiments, the apertures 160 b mayhave an area greater than the apertures 160 c. The dimensions of thebase layer 132 may be increased or decreased, for example, substantiallyin proportion to one another to suit a particular application. Further,although the central portion 156, the border 161, and the periphery 152of the base layer 132 are shown as having a substantially square shape,these and other components of the base layer 132 may have any shape tosuit a particular application.

The base layer 132 may be a soft, pliable material suitable forproviding a fluid seal with the tissue site 104 as described herein. Forexample, the base layer 132 may comprise a silicone gel, a softsilicone, hydrocolloid, hydrogel, polyurethane gel, polyolefin gel,hydrogenated styrenic copolymer gel, a foamed gel, a soft closed cellfoam such as polyurethanes and polyolefins coated with an adhesive asdescribed below, polyurethane, polyolefin, or hydrogenated styreniccopolymers. In some embodiments, the base layer 132 may include asilicone such as Scapa Soft-Pro®. The base layer 132 may have athickness between about 500 microns (μm) and about 1000 microns (μm). Insome embodiments, the base layer 132 may have a stiffness between about5 Shore OO and about 80 Shore OO. Further, in some embodiments, the baselayer 132 may be comprised of hydrophobic or hydrophilic materials.

In some embodiments (not shown), the base layer 132 may be ahydrophobic-coated material. For example, the base layer 132 may beformed by coating a spaced material, such as, for example, woven,nonwoven, molded, or extruded mesh with a hydrophobic material. Thehydrophobic material for the coating may be a soft silicone, forexample. The base layer 132 may additionally or alternatively be anon-adherent copolymer mesh. In this manner, the adhesive 136 may extendthrough openings in the spaced material analogous to the apertures 160.

In some embodiments, the adhesive 136 may be exposed to the apertures160 in at least the periphery 152 of the base layer 132. Further, insome embodiments, the adhesive 136 may be positioned adjacent to, orpositioned in fluid communication with, the apertures 160 in at leastthe periphery 152 of the base layer 132. Further, in some embodiments,the adhesive 136 may be exposed to or in fluid communication with tissuesurrounding the tissue site 104 through the apertures 160 in the baselayer 132. As described herein and shown in FIG. 15 , the adhesive 136may extend, deform, or be pressed through the plurality of apertures 160to contact the epidermis 106 for securing the dressing 324 to, forexample, tissue surrounding the tissue site 104. The apertures 160 mayprovide sufficient contact of the adhesive 136 to the epidermis 106 tosecure the dressing 124 about the tissue site 104. However, theconfiguration of the apertures 160 and the adhesive 136, describedherein, may permit release and repositioning of the dressing 324 aboutthe tissue site 104.

In some embodiments, the apertures 160 b at the corners 158 of theperiphery 152 may be smaller than the apertures 160 a in other portionsof the periphery 152. For a given geometry of the corners 158, thesmaller size of the apertures 160 b compared to the apertures 160 a mayenhance or increase the surface area of the adhesive 136 exposed to theapertures 160 b and to tissue through the apertures 160 b at the corners158. The size and number of the apertures 160 b in the corners 158 maybe adjusted as necessary, depending on the chosen geometry of thecorners 158, to enhance or increase the exposed surface area of theadhesive 136 as described above.

Similar to the apertures 160 b in the corners 158, any of the apertures160 may be adjusted in size and number to increase the surface area ofthe adhesive 136 exposed to or in fluid communication with the apertures160 for a particular application or geometry of the base layer 132. Forexample, in some embodiments (not shown) the apertures 160 b, orapertures of another size, may be positioned in the periphery 152 and atthe border 161. Similarly, the apertures 160 b, or apertures of anothersize, may be positioned as described above in other locations of thebase layer 132 that may have a complex geometry or shape.

The adhesive 136 may be a medically-acceptable adhesive. In someembodiments, the adhesive 136 may be deformable or flowable. Forexample, the adhesive 136 may comprise an acrylic adhesive, rubberadhesive, high-tack silicone adhesive, polyurethane, or other adhesivesubstance. In some embodiments, the adhesive 136 may be apressure-sensitive adhesive comprising an acrylic adhesive. The adhesive136 may be a layer having substantially the same shape as the periphery152 of the base layer 132. In some embodiments, the adhesive 136 may becontinuous or discontinuous. Discontinuities in the adhesive 136 may beprovided by apertures (not shown) in the adhesive 136. Apertures in theadhesive 136 may be formed after application of the adhesive 136 or bycoating the adhesive 136 in patterns on a carrier layer, such as, forexample, a side of the sealing member 140 adapted to face the epidermis106. Further, apertures in the adhesive 136 may be sized to control theamount of the adhesive 136 extending through the apertures 160 in thebase layer 132 to reach the epidermis 106. Apertures in the adhesive 136may also be sized to enhance the Moisture Vapor Transfer Rate (MVTR) ofthe dressing 124, described further herein.

Factors that may be utilized to control the adhesion strength of thedressing 324 may include the diameter, area, and number of the apertures160 in the base layer 132, the thickness of the base layer 132, thethickness and amount of the adhesive 136, and the tackiness of theadhesive 136. An increase in the amount of the adhesive 136 extendingthrough the apertures 160 may correspond to an increase in the adhesionstrength of the dressing 324. A decrease in the thickness of the baselayer 132 may correspond to an increase in the amount of adhesive 136extending through the apertures 160. Thus, the diameter, area, andconfiguration of the apertures 160, the thickness of the base layer 132,and the amount and tackiness of the adhesive utilized may be varied toprovide a desired adhesion strength for the dressing 324.

In some embodiments, the tackiness of the adhesive 136 may vary indifferent locations of the base layer 132. For example, in locations ofthe base layer 132 where the apertures 160 are comparatively large, suchas the apertures 160 a, the adhesive 136 may have a lower tackiness thanother locations of the base layer 132 where the apertures 160 aresmaller, such as the apertures 160 b and 160 c. In this manner,locations of the base layer 132 having larger apertures 160 and lowertackiness adhesive 136 may have an adhesion strength comparable tolocations having smaller apertures 160 and higher tackiness adhesive136.

A release liner 162 may be attached to or positioned adjacent to thebase layer 132 to protect the adhesive 136 prior to application of thedressing 324 to the tissue site 104. Prior to application of thedressing 324 to the tissue site 104, the base layer 132 may bepositioned between the sealing member 140 and the release liner 162.Removal of the release liner 162 may expose the base layer 132 and theadhesive 136 for application of the dressing 324 to the tissue site 104.The release liner 162 may also provide stiffness to assist with, forexample, deployment of the dressing 324. The release liner 162 may be,for example, a casting paper, a film, or polyethylene. Further, therelease liner 162 may be a polyester material such as polyethyleneterephthalate (PET), or similar polar semi-crystalline polymer. The useof a polar semi-crystalline polymer for the release liner 162 maysubstantially preclude wrinkling or other deformation of the dressing324. For example, the polar semi-crystalline polymer may be highlyorientated and resistant to softening, swelling, or other deformationthat may occur when brought into contact with components of the dressing324, or when subjected to temperature or environmental variations, orsterilization. Further, a release agent may be disposed on a side of therelease liner 162 that is configured to contact the base layer 132. Forexample, the release agent may be a silicone coating and may have arelease factor suitable to facilitate removal of the release liner 162by hand and without damaging or deforming the dressing 324. In someembodiments, the release agent may be fluorosilicone. In otherembodiments, the release liner 162 may be uncoated or otherwise usedwithout a release agent. In some embodiments, the base layer 132 may beadapted to be positioned in direct contact with the tissue site 104. Insome embodiments, the base layer 132 may include a non-adherent mesh andone or more wicking layers of the dressing as discussed herein may bepositioned between the base layer 132 and a dressing sealing member asdiscussed herein.

Continuing with FIGS. 13-16B, the sealing member 140 may also bereferred to as a dressing sealing member 140. The sealing member 140 mayhave a periphery 164 and a central portion 168. The sealing member 140may additionally include an aperture 170. The periphery 164 of thesealing member 140 may be positioned proximate to the periphery 152 ofthe base layer 132 such that the central portion 168 of the sealingmember 140 and the central portion 156 of the base layer 132 define anenclosure 172. The adhesive 136 may be positioned at least between theperiphery 164 of the sealing member 140 and the periphery 152 of thebase layer 132. The sealing member 140 may cover the tissue site 104 andthe interface manifold 120 to provide a fluid seal and a sealed space174 between the tissue site 104 and the sealing member 140 of thedressing 324. Further, the sealing member 140 may cover other tissue,such as a portion of the epidermis 106, surrounding the tissue site 104to provide the fluid seal between the sealing member 140 and the tissuesite 104. In some embodiments, a portion of the periphery 164 of thesealing member 140 may extend beyond the periphery 152 of the base layer132 and into direct contact with tissue surrounding the tissue site 104.In other embodiments, the periphery 164 of the sealing member 140, forexample, may be positioned in contact with tissue surrounding the tissuesite 104 to provide the sealed space 174 without the base layer 132.Thus, the adhesive 136 may also be positioned at least between theperiphery 164 of the sealing member 140 and tissue, such as theepidermis 106, surrounding the tissue site 104. The adhesive 136 may bedisposed on a surface of the sealing member 140 adapted to face thetissue site 104 and the base layer 132.

The sealing member 140 may be formed from any material that allows for afluid seal. A fluid seal may be a seal adequate to maintain reducedpressure at a desired site given the particular reduced pressure sourceor system involved. The sealing member 140 may comprise, for example,one or more of the following materials: hydrophilic polyurethane;cellulosics; hydrophilic polyamides; polyvinyl alcohol; polyvinylpyrrolidone; hydrophilic acrylics; hydrophilic silicone elastomers; anINSPIRE 2301 material from Expopack Advanced Coatings of Wrexham, UnitedKingdom having, for example, an MVTR (inverted cup technique) of 14400g/m²/24 hours and a thickness of about 30 microns; a thin, uncoatedpolymer drape; natural rubbers; polyisoprene; styrene butadiene rubber;chloroprene rubber; polybutadiene; nitrile rubber; butyl rubber;ethylene propylene rubber; ethylene propylene diene monomer;chlorosulfonated polyethylene; polysulfide rubber; polyurethane (PU);EVA film; co-polyester; silicones; a silicone drape; a 3M Tegaderm®drape; a polyurethane (PU) drape such as one available from AveryDennison Corporation of Pasadena, Calif.; a polyurethane (PU) film suchas Scapa Bioflex 130 polyurethane Film®; polyether block polyamidecopolymer (PEBAX), for example, from Arkema, France; Expopack 2327; orother appropriate material.

The sealing member 140 may be vapor permeable and liquid impermeable,thereby allowing vapor and inhibiting liquids from exiting the sealedspace 174 provided by the dressing 324. In some embodiments, the sealingmember 140 may be a flexible, breathable film, membrane, or sheet havinga high MVTR of, for example, at least about 300 g/m² per 24 hours. Inother embodiments, a low or no vapor transfer drape may be used. Thesealing member 140 may comprise a range of medically suitable filmshaving a thickness between about 15 microns (μm) to about 50 microns(μm).

The fluid management assembly 344 may be disposed in the enclosure 172.In some embodiments, the fluid management assembly 344 may include oneor more dressing wicking layers 345. For example, a first dressingwicking layer 376, a second dressing wicking layer 378, and a thirddressing wicking layer 381. The one or more dressing wicking layers 345may wick fluid along a surface of one or more of the first dressingwicking layer 376, the second dressing wicking layer 378, and the thirddressing wicking layer 381. For example, one or more dressing wickinglayer 345 may wick or otherwise transport fluid in a lateral directionalong the surfaces of one of the first dressing wicking layer 376, thesecond dressing wicking layer 378, or the third dressing wicking layer381, respectively. The surface of the first dressing wicking layer 376may be normal relative to the thickness of the first dressing wickinglayer 176. The surface of the second dressing wicking layer 378 may benormal relative to the thickness of the second dressing wicking layer378. The surface of the third dressing wicking layer 381 may be normalrelative to the thickness of the third dressing wicking layer 381. Thewicking of fluid along the one or more dressing wicking layers 345 mayenhance the distribution of the fluid. A laminate combination of thefirst dressing wicking layer 376, the second dressing wicking layer 378,and the third dressing wicking layer 381 may be adapted as describedherein to maintain an open structure, resistant to blockage, capable ofmaintaining fluid communication with, for example, the tissue site 104.

Referring to the embodiments of the fluid management assembly 344depicted in FIGS. 13, 14, and 17 , a peripheral portion 186 of the firstdressing wicking layer 376 may be coupled to a peripheral portion 187 ofthe third dressing wicking layer 381 to define a wicking layer enclosure389 between the first dressing wicking layer 376 and the third dressingwicking layer 381. In some embodiments, the wicking layer enclosure 389may surround or otherwise encapsulate the second dressing wicking layer378 between the first dressing wicking layer 376 and the third dressingwicking layer 381. Materials suitable for the first dressing wickinglayer 376, the second dressing wicking layer 378, and the third dressingwicking layer 381 may include, without limitation, any material having agrain structure capable of wicking fluid as described herein, such as,for example, LIBELTEX TDL2, 80 gsm, or similar materials, which may benon-woven.

The fluid management assembly 344 may be manufactured as a pre-laminatedstructure, or supplied as individual layers of material that can bestacked upon one another as described above. Individual layers of thefluid management assembly 344 may be bonded or otherwise secured to oneanother without adversely affecting fluid management by, for example,utilizing a solvent or non-solvent adhesive, or by thermal welding.Further, the fluid management assembly 344 may be coupled to the border161 of the base layer 132 in any suitable manner, such as, for example,by a weld or an adhesive. The border 161, being free of the apertures160 as described above, may provide a flexible barrier between the fluidmanagement assembly 344 and the tissue site 104 for enhancing comfort.In some embodiments, the base layer 132 may include a non-adherentinterface. The non-adherent interface may be used with VLUs toaccommodate a sensitive and/or a sore tissue site. The non-adherentinterface may include a co-polymer mesh.

The dressing 324 may be modified in various embodiments to suit aparticular application. The first dressing wicking layer 376, the seconddressing wicking layer 378, and the third dressing wicking layer 381 maywick or draw fluid away from the tissue site 104 for transport to alocation exterior to the dressing 324. Further, the configuration of thefirst dressing wicking layer 376, the second dressing wicking layer 378,and the third dressing wicking layer 381 described herein may preferencefluid away from the tissue site 104 and prevent the fluid from returningto the tissue site 104 prior to removal of the fluid from the dressing324, for example, by the application of reduced pressure. The wickinglayer enclosure 389 may enhance this ability to preference fluid awayfrom the tissue site 104 and to prevent the fluid from returning to thetissue site 104. In some embodiments, the dressing 324 may comprise awinged profile to allow for greater adhesion between the dressing 324and a leg or an arm, for example.

The dressing 324 may be further modified in various embodiments that maybe suitable for some applications that communicate fluid from the tissuesite 104 exterior to the dressing 324. For example, the fluid managementassembly 344 may be omitted from the dressing 324, and a dressingmanifold (not shown) may be positioned in the enclosure 172 in place ofthe fluid management assembly 344. The dressing manifold may beconfigured as a layer and may be comprised of any material suitable forremoving fluids from a tissue site through a plurality of pores,pathways, or flow channels as described herein, such as, withoutlimitation, a foam, a woven material, a cast silicone, a polyurethanematerial, or any of the materials recited above for the interfacemanifold 120. Further, in some embodiments, the dressing 324 may bemodified by omitting the base layer 132 and replacing the fluidmanagement assembly 344 with the above-described dressing manifold. Insuch an embodiment, the dressing 324 may comprise the sealing member 140and the dressing manifold for disposing in the sealed space 174 betweenthe sealing member 140 and the tissue site 104.

In some embodiments, the fluid management assembly 344 may include afilm, a first wicking layer, and a second wicking layer. The film may bea base layer of adhesive coated polyurethane (PU) film. The adhesivecoated on the film may adhere the first wicking layer to an innersurface of the fluid management assembly (i.e. a surface forming thewicking layer enclosure 188 and exposed to the wicking layer enclosure188). The first wicking layer may be stacked or placed below orunderneath the second wicking layer such that fluid (such a fluid ofexudate) is communicated from the first wicking layer to the secondwicking layer and out the conduit interface 148. The first wicking layermay have a wider base and a higher density relative to the secondwicking layer. The first wicking layer may have a surface area that isgreater than a surface area of the second wicking layer. The firstwicking layer may have a greater thickness (such as 50 mm) relative tothe second wicking layer thickness (such as 20 mm). The first wickinglayer may include a profile to spread the fluid out over an entiresurface of the first wicking layer to increase evaporation. The secondwicking layer may be used to pull fluid from the wound towards to theconduit interface 148. In some embodiments, the second wicking layer mayalternatively or additionally include a profile like the profile of thefirst wicking layer to spread fluid out over an entire surface of thesecond wicking layer. The profile of the second wicking layer may alsobe used to increase evaporation. In some embodiments, the fluidmanagement assembly 344 may include a film positioned to adhere to thesecond wicking layer on a surface of the second wicking layer oppositethe first wicking layer. The film positioned to adhere to the secondwicking layer may include one or more of the same properties as the filmthat may adhere to the first wicking layer described herein.

Referring to FIGS. 13, 14, and 18 , the conduit interface 148 may bepositioned proximate to the sealing member 140 and in fluidcommunication with the enclosure 172 of the dressing 324. For example,the conduit interface 148 may be in fluid communication with thedressing 324 through the aperture 170 in the sealing member 140. Theconduit interface 148 may provide reduced pressure from thereduced-pressure source 128 to the dressing 324. The conduit interface148 may also be adapted to be positioned in fluid communication with theoptional interface manifold 120. An optional liquid trap 192 may bepositioned in fluid communication between the dressing 324 and thereduced-pressure source 128. The liquid trap 192 may be any suitablecontainment device having a sealed internal volume capable of retainingliquid, such as condensate or other liquids.

The conduit interface 148 may comprise a medical-grade, soft polymer orother pliable material. As non-limiting examples, the conduit interface148 may be formed from polyurethane, polyethylene, polyvinyl chloride(PVC), fluorosilicone, or ethylene-propylene. In some illustrative,non-limiting embodiments, conduit interface 148 may be molded fromDEHP-free PVC. The conduit interface 148 may be formed in any suitablemanner such as by molding, casting, machining, or extruding. Further,the conduit interface 148 may be formed as an integral unit or asindividual components and may be coupled to the dressing 324 by, forexample, adhesive or welding.

In some embodiments, the conduit interface 148 may be formed of anabsorbent material having absorbent and evaporative properties. Theabsorbent material may be vapor permeable and liquid impermeable,thereby being configured to permit vapor to be absorbed into andevaporated from the material through permeation while inhibitingpermeation of liquids. The absorbent material may be, for example, ahydrophilic polymer such as a hydrophilic polyurethane. Although theterm hydrophilic polymer may be used in the illustrative embodimentsthat follow, any absorbent material having the properties describedherein may be suitable for use in the system 302. Further, the absorbentmaterial or hydrophilic polymer may be suitable for use in variouscomponents of the system 302 as described herein.

The use of such a hydrophilic polymer for the conduit interface 148 maypermit liquids in the conduit interface 148 to evaporate, or otherwisedissipate, during operation. For example, the hydrophilic polymer mayallow the liquid to permeate or pass through the conduit interface 148as vapor, in a gaseous phase, and evaporate into the atmosphere externalto the conduit interface 148. Such liquids may be, for example,condensate or other liquids. Condensate may form, for example, as aresult of a decrease in temperature within the conduit interface 148, orother components of the system 302, relative to the temperature at thetissue site 104. Removal or dissipation of liquids from the conduitinterface 148 may increase visual appeal and prevent odor. Further, suchremoval of liquids may also increase efficiency and reliability byreducing blockages and other interference with the components of thesystem 302.

Similar to the conduit interface 148, the liquid trap 192, and othercomponents of the system 302, may also be formed of an absorbentmaterial or a hydrophilic polymer. The absorptive and evaporativeproperties of the hydrophilic polymer may also facilitate removal anddissipation of liquids residing in the liquid trap 192, and othercomponents of the system 302, by evaporation. Such evaporation may leavebehind a substantially solid or gel-like waste. The substantially solidor gel-like waste may be cheaper to dispose than liquids, providing acost savings for operation of the system 302. The hydrophilic polymermay be used for other components in the system 302 where the managementof liquids is beneficial.

In some embodiments, the absorbent material or hydrophilic polymer mayhave an absorbent capacity in a saturated state that is substantiallyequivalent to the mass of the hydrophilic polymer in an unsaturatedstate. The hydrophilic polymer may be fully saturated with vapor in thesaturated state and substantially free of vapor in the unsaturatedstate. In both the saturated state and the unsaturated state, thehydrophilic polymer may retain substantially the same physical,mechanical, and structural properties. For example, the hydrophilicpolymer may have a hardness in the unsaturated state that issubstantially the same as a hardness of the hydrophilic polymer in thesaturated state. The hydrophilic polymer and the components of thesystem 302 incorporating the hydrophilic polymer may also have a sizethat is substantially the same in both the unsaturated state and thesaturated state. Further, the hydrophilic polymer may remain dry, coolto the touch, and pneumatically sealed in the saturated state and theunsaturated state. The hydrophilic polymer may also remain substantiallythe same color in the saturated state and the unsaturated state. In thismanner, this hydrophilic polymer may retain sufficient strength andother physical properties to remain suitable for use in the system 302.An example of such a hydrophilic polymer is offered under the trade nameTechophilic HP-93A-100, available from The Lubrizol Corporation ofWickliffe, Ohio, United States. Techophilic HP-93A-100 is an absorbenthydrophilic thermoplastic polyurethane capable of absorbing 100% of theunsaturated mass of the polyurethane in water and having a durometer orShore Hardness of about 83 Shore A.

The conduit interface 148 may carry an odor filter 194 adapted tosubstantially preclude the passage of odors from the tissue site 104 outof the sealed space 174. Further, the conduit interface 148 may carry aprimary hydrophobic filter 195 adapted to substantially preclude thepassage of liquids through the primary hydrophobic filter 195. The odorfilter 194 and the primary hydrophobic filter 195 may be disposed in theconduit interface 148 or other suitable location such that fluidcommunication between the reduced-pressure source 128, or optionaltherapy unit 130, and the dressing 324 is provided through the odorfilter 194 and the primary hydrophobic filter 195. In some embodiments,the odor filter 194 and the primary hydrophobic filter 195 may besecured within the conduit interface 148 in any suitable manner, such asby adhesive or welding. In other embodiments, the odor filter 194 or theprimary hydrophobic filter 195 may be omitted, or positioned proximateto any exit location in the system 302 or the dressing 324 that is influid communication with the atmosphere, the reduced-pressure source128, or the optional therapy unit 130.

The odor filter 194 may be comprised of a carbon material in the form ofa layer or particulate. For example, the odor filter 194 may comprise awoven carbon cloth filter such as those manufactured by ChemvironCarbon, Ltd. of Lancashire, United Kingdom. The primary hydrophobicfilter 195 may be comprised of a material that is liquid impermeable andvapor permeable. For example, the primary hydrophobic filter 195 maycomprise a material manufactured under the designation MMT-314 by W.L.Gore & Associates, Inc. of Newark, Del., United States, or similarmaterials. The primary hydrophobic filter 195 may be provided in theform of a membrane or layer.

Continuing with FIGS. 13, 14, and 18 , the reduced-pressure source 128may provide reduced pressure to the dressing 324 and the sealed space174. The reduced-pressure source 128 may be any suitable device forproviding reduced pressure, such as, for example, a vacuum pump, wallsuction, hand pump, manual pump, or other source. In some embodiments,the reduced-pressure source 128 may be a component of the therapy unit130. The therapy unit 130 may include control circuitry and sensors,such as a pressure sensor, that may be configured to monitor reducedpressure at the tissue site 104. The therapy unit 130 may also beconfigured to control the amount of reduced pressure from thereduced-pressure source 128 being applied to the tissue site 104according to a user input and a reduced-pressure feedback signalreceived from the tissue site 104. In some embodiments, the reducedpressure source 128 (such as a manual pump, hand pump, or the like) maycomprise a container or may be fluidly connected to a container thatreceives fluid collected from the tissue site 104. Thus, when thereduced pressure source 128 generates reduced pressure, fluid may becommunicated from the tissue site, through the dressing, through thebridge, and received and stored in the container of the reduced pressuresource 128 or fluidly connected to the reduced pressure source 128.

As used herein, “reduced pressure” may refer to a pressure less than theambient pressure at a tissue site being subjected to treatment. In someembodiments, the reduced pressure may be less than the atmosphericpressure. Further, in some embodiments, the reduced pressure may also beless than a hydrostatic pressure at a tissue site. Unless otherwiseindicated, values of pressure stated herein are gauge pressures. Whilethe amount and nature of reduced pressure applied to a tissue site mayvary according to the application, in some embodiments, the reducedpressure may be between −5 mm Hg and −500 mm Hg. In some embodiments,the reduced pressure may be between −100 mm Hg and −200 mm Hg.

The reduced pressure delivered may be, for example, constant, varied,patterned, or random. Further, the reduced pressure may be deliveredcontinuously or intermittently. Although the terms “vacuum” and“negative pressure” may be used to describe the pressure applied to atissue site, the actual pressure applied to the tissue site may be morethan the pressure normally associated with a complete vacuum. Consistentwith the use herein, an increase in reduced pressure or vacuum pressuremay refer to a relative reduction in absolute pressure. Further, anincrease in reduced pressure may correspond to a reduction in pressure(more negative relative to ambient pressure), and a decrease in reducedpressure may correspond to an increase in pressure (less negativerelative to ambient pressure).

Referring to FIGS. 13 and 18 , a conduit 196 having an internal lumen197 may be coupled in fluid communication between the reduced-pressuresource 128 and the dressing 324. The internal lumen 197 may have aninternal diameter between about 0.5 millimeters to about 3.0millimeters. In some embodiments, the internal diameter of the internallumen 197 may be between about 1 millimeter to about 2 millimeters. Theconduit interface 148 may be coupled in fluid communication with thedressing 324 and adapted to connect between the conduit 196 and thedressing 324 for providing fluid communication with the reduced-pressuresource 128. The conduit interface 148 may be fluidly coupled to theconduit 196 in any suitable manner, such as, for example, by anadhesive, solvent or non-solvent bonding, welding, or interference fit.The aperture 170 in the sealing member 140 may provide fluidcommunication between the dressing 324 and the conduit interface 148.For example, the conduit interface 148 may be in fluid communicationwith the enclosure 172 or the sealed space 174 through the aperture 170in the sealing member 140. In some embodiments, the conduit 196 may beinserted into the dressing 324 through the aperture 170 in the sealingmember 140 to provide fluid communication with the reduced-pressuresource 128 without use of the conduit interface 148. Thereduced-pressure source 128 may also be directly coupled in fluidcommunication with the dressing 324 or the sealing member 140 withoutuse of the conduit 196. In some embodiments, the conduit 196 may be, forexample, a flexible polymer tube. A distal end of the conduit 196 mayinclude a coupling 198 for attachment to the reduced-pressure source128.

The conduit 196 may have a secondary hydrophobic filter 199 disposed inthe internal lumen 197 such that fluid communication between thereduced-pressure source 128 and the dressing 324 is provided through thesecondary hydrophobic filter 199. The secondary hydrophobic filter 199may be, for example, a porous, sintered polymer cylinder sized to fitthe dimensions of the internal lumen 197 to substantially precludeliquid from bypassing the cylinder. The secondary hydrophobic filter 199may also be treated with an absorbent material adapted to swell whenbrought into contact with liquid to block the flow of the liquid. Thesecondary hydrophobic filter 199 may be positioned at any locationwithin the internal lumen 197. However, positioning the secondaryhydrophobic filter 199 within the internal lumen 197 closer toward thereduced-pressure source 128, rather than the dressing 324, may allow auser to detect the presence of liquid in the internal lumen 197.

In some embodiments, the conduit 196 and the coupling 198 may be formedof an absorbent material or a hydrophilic polymer as described above forthe conduit interface 148. In this manner, the conduit 196 and thecoupling 198 may permit liquids in the conduit 196 and the coupling 198to evaporate, or otherwise dissipate, as described above for the conduitinterface 148. The conduit 196 and the coupling 198 may be, for example,molded from the hydrophilic polymer separately, as individualcomponents, or together as an integral component. Further, a wall of theconduit 196 defining the internal lumen 197 may be extruded from thehydrophilic polymer. The conduit 196 may be less than about 1 meter inlength, but may have any length to suit a particular application.

Referring to FIG. 19 , another embodiment of a fluid management assembly444 suitable for use with the dressing 424 and the system 402 is shown.The fluid management assembly 444 may include one or more dressingwicking layers 484 such as a first dressing wicking layer 476, a seconddressing wicking layer 478, and a third dressing wicking layer 480comprised of substantially the same materials and properties as thosedescribed above in connection with the fluid management assembly 144.Thus, the first dressing wicking layer 476, the second dressing wickinglayer 478, and the third dressing wicking layer 480 may be analogous tothe first dressing wicking layer 376, the second dressing wicking layer378, and the third dressing wicking layer 381, respectively.

In the fluid management assembly 444, the third dressing wicking layer480 may have a peripheral portion 287. The third dressing wicking layer480 and the peripheral portion 287 of the first dressing wicking layer476 may be positioned in contact with the sealing member 140. The seconddressing wicking layer 478 may have a peripheral portion 285 extendingbeyond the peripheral portion 287 of the third dressing wicking layer480. The second dressing wicking layer 478 may be positioned adjacent toor proximate to the first dressing wicking layer 280 such that theperipheral portion 285 of the second dressing wicking layer 478 is incontact with the sealing member 140 surrounding the peripheral portion287 of the third dressing wicking layer 480. Similarly, the firstdressing wicking layer 476 may have a peripheral portion 286 extendingbeyond the peripheral portion 285 of the second dressing wicking layer478. The first dressing wicking layer 476 may be positioned adjacent toor proximate to the second dressing wicking layer 478 such that theperipheral portion 286 of the first dressing wicking layer 476 is incontact with the sealing member 140 surrounding the peripheral portion285 of the second dressing wicking layer 478. Further, the firstdressing wicking layer 476 may be positioned adjacent to or proximate tothe base layer 132. Thus, at least the peripheral portion 287, theperipheral portion 285, and the peripheral portion 286 may be coupled tothe sealing member 140, such as, for example, by an adhesive coatingdisposed on a surface of the sealing member 140 facing the base layer132. The adhesive coating may be analogous to the adhesive 136 that maybe applied across the surface of the sealing member 140 facing the baselayer 132. The third dressing wicking layer 480, the second dressingwicking layer 478, and the first dressing wicking layer 476 mayrespectively have increasing surface areas to enhance contact with theadhesive coating described above. In other embodiments, the fluidmanagement assembly 444 may include any number of absorbent layers andwicking layers for treating a particular tissue site.

In operation, according to some illustrative embodiments, the interfacemanifold 120 may be disposed against or proximate to the tissue site104. The dressing 324, 424 may be applied over or covering the interfacemanifold 120 and the tissue site 104 to form the sealed space 174. Forexample, the base layer 132 may be applied covering the interfacemanifold 120 and tissue surrounding the tissue site 104. The materialsdescribed above for the base layer 132 may have a tackiness that mayhold the dressing 324 or 424 initially in position. The tackiness may besuch that if an adjustment is desired, the dressing 324, 424 may beremoved and reapplied. Once the dressing 324, 424 is in the desiredposition, a force may be applied, such as hand pressure, on a side ofthe sealing member 140 facing outward or opposite the tissue site 104.The force applied to the sealing member 140 may cause at least someportion of the adhesive 136 to penetrate or extend through the pluralityof apertures 160 and into contact with tissue surrounding the tissuesite 104, such as the epidermis 106, to releasably adhere the dressing324, 424 about the tissue site 104. In this manner, the configuration ofthe dressing 324, 424 described herein may provide an effective andreliable seal against challenging anatomical surfaces, such as an elbowor heal, at and around the tissue site 104. Further, the dressing 324,424 may permit re-application or re-positioning to, for example, correctair leaks caused by creases and other discontinuities in the dressing324, 424 and the tissue site 104. The ability to rectify leaks mayincrease the reliability of the therapy and reduce power consumption.

As the dressing 324, 424 comes into contact with fluid from the tissuesite 104, the fluid may move through the apertures 160 toward the fluidmanagement assembly 344, 444. The fluid management assembly 344, 444 maywick or otherwise move the fluid away from the tissue site 104, andthrough the interface manifold 120, if equipped. As described above, theinterface manifold 120 may be adapted to communicate fluid from thetissue site 104 rather than store the fluid. Thus, the fluid managementassembly 344, 444 may be adapted to wick, pull, draw, or otherwiseattract fluid from the tissue site 104 through the interface manifold120. In the fluid management assembly 344, 444 the fluid may initiallycome into contact with the first dressing wicking layer 376, 476. Thefirst dressing wicking layer 376, 476 may distribute the fluid laterallyalong the surface of the first dressing wicking layer 376, 476 forabsorption or removal from the dressing 324, 424. Similarly, fluid maycome into contact with the third dressing wicking layer 381, 480 and maybe distributed laterally along the surface of the third dressing wickinglayer 381, 480 for absorption or removal from the dressing 324, 424.

Referring to FIGS. 21-23 , in some embodiments, a bridge assembly 710may extend away from the tissue site 104 and the dressing 124, 324, 424to define a fluid passageway between the tissue site 104 and thereduced-pressure source 128. For example, the bridge assembly 710 may becoupled in fluid communication between the dressing 124, 324, 424 andthe reduced-pressure source 128. However, other applications for thebridge assembly 710 are possible. In some embodiments, the bridgeassembly 710 may include a bridge 720, a sealing apparatus 730, and theconduit interface 148.

The bridge 720 may include a receiving end 734 separated or spaced apartfrom a transmitting end 738 by a length 740. The receiving end 734 mayhave a receiving end aperture 742, and the transmitting end 738 may havea transmitting end aperture 746. The receiving end 734 and the receivingend aperture 742 may be in fluid communication with the transmitting end738 and the transmitting end aperture 746 through the length 740 of thebridge 720.

The conduit interface 148 may be adapted to be fluidly coupled to thereceiving end 734 of the bridge 720 through, for example, the receivingend aperture 742. Thus, the conduit interface 148 may be in fluidcommunication with the transmitting end 738 through the length 740 ofthe bridge 720. The sealing apparatus 730 may be positioned about thetransmitting end aperture 746 and between the transmitting end 738 andthe dressing 124, 324, 424 for coupling the transmitting end 738 to thedressing 124, 324, 424 and in fluid communication with the dressing 124through the transmitting end aperture 746. Thus, the conduit interface148 may be positioned in fluid communication with the dressing 124, 324,424 through the bridge 720. The sealing apparatus 730 may be anysuitable device for making the connections described above, such as,without limitation, an adhesive ring or weld.

In some embodiments, the bridge 720 may include one or more wickinglayers 754, and a bridge sealing member 758. The bridge sealing member758 may extend along the length 740 of the bridge 720. Further, thebridge sealing member 758 may define an internal passageway 784. The oneor more wicking layers 754 may be disposed within the internalpassageway 784 of the bridge sealing member 758. In some embodiments,the bridge sealing member 758 may entirely surround the one or morewicking layers 754. Further, in some embodiments, the bridge sealingmember 758 may encapsulate the one or more wicking layers 754.

In some embodiments, the one or more wicking layers 754 may include atleast one of a first wicking layer 780, a second wicking layer 781, or athird wicking layer 782. In some embodiments, the first wicking layer780, the second wicking layer 781, and the third wicking layer 782 maybe referred to as a first bridge wicking layer, a second bridge wickinglayer, and a third bridge wicking layer, respectively. Each of the oneor more wicking layers 754 may extend along the length 740 of the bridge720, and may be disposed within the internal passageway 784 that may bedefined by the bridge sealing member 758. The first wicking layer 780,the second wicking layer 781, and the third wicking layer 782 may eachbe comprised of the same materials recited above for the first dressingwicking layer 176 and the second dressing wicking layer 180.

A periphery or edge of the first wicking layer 780 may be coupled to aperiphery or edge of the second wicking layer 781 in any suitablemanner, such as, for example, by a weld 786, to define the internalpassageway 784 of the bridge envelope 750. A periphery or edge of thesecond wicking layer 781 may be coupled to a periphery or edge of thethird wicking layer 782 in any suitable manner, such as, for example, bya weld 786, to define the internal passageway 784 of the bridge sealingmember 758. The second wicking layer 781 may be positioned between thefirst wicking layer 780 and the third wicking layer 782. In someembodiments, the one or more wicking layers 754 (such as the firstwicking layer 780, the second wicking layer 781, and the third wickinglayer 782) may be positioned and sealed between the first sealing layer788 and the second sealing layer 790 without a weld (such as weld 786)coupling the one or more wicking layers 754. In some embodiments, theone or more wicking layer 754 may be separated from each other or may beheld together using

The first wicking layer 780, the second wicking layer 781, and the thirdwicking layer 782 may each include a fluid acquisition surface 772 and afluid distribution surface 774. The fluid distribution surface 774 maybe positioned on an opposite side of the first wicking layer 780, thesecond wicking layer 781, and the third wicking layer 782 from the fluidacquisition surface 772. The fluid acquisition surface 772 of each ofthe first wicking layer 780, the second wicking layer 781, and the thirdwicking layer 782 may face in a direction of the first sealing layer788. Further, the fluid distribution surface 774 of each of the firstwicking layer 780, the second wicking layer 781, and the third wickinglayer 782 may face in a direction of the second sealing layer 790. Thefluid acquisition surface 772 of each of the first wicking layer 780,the second wicking layer 781, and the third wicking layer 782 may facein a direction of the second sealing layer 790. The fluid distributionsurface 774 of each of the first wicking layer 780, the second wickinglayer 781, and the third wicking layer 782 may face in a direction ofthe first sealing layer 788. In some embodiments, a fluid acquisitionsurface 772 of the first wicking layer 780 may face a fluid acquisitionsurface 772 of the second wicking layer 781. In some embodiments, afluid acquisition surface 772 of the second wicking layer 781 may face afluid acquisition surface 772 of the third wicking layer 782. In someembodiments, a fluid distribution surface 774 of the first wicking layer780 may face a fluid distribution surface 774 of the second wickinglayer 781. In some embodiments, a fluid distribution surface 774 of thesecond wicking layer 781 may face a fluid distribution surface 774 ofthe third wicking layer 782.

In some embodiments, at least a portion of the first wicking layer 780may be in direct contact with at least a portion of the second wickinglayer 781. In some embodiments, at least a portion of the first wickinglayer 780 may be spaced apart or separated from the second wicking layer781 by an internal volume 760. In some embodiments, at least a portionof the second wicking layer 781 may be in direct contact with at least aportion of the third wicking layer 782. In some embodiments, at least aportion of the second wicking layer 781 may be spaced apart or separatedfrom the third wicking layer 782 by an internal volume 706. In someembodiments, the fluid distribution surface 774 may include a pluralityof longitudinal fibers 791 oriented substantially in a longitudinaldirection along the length 740 of the bridge 720. Further, in someembodiments, the fluid acquisition surface 772 may include a pluralityof vertical fibers 793 oriented substantially normal relative to thelongitudinal fibers 791.

In some embodiments, the one or more wicking layers 754 may include afirst set of one or more bridge wicking layers and a second set of oneor more bridge wicking layers. The first set of one or more bridgewicking layers and the second set of one or more bridge wicking layersmay each extend along the length 740 of the storage bridge 720, and maybe disposed within an internal passageway 784 that may be defined by thebridge sealing member 758. A periphery or edge of at least one bridgewicking layer of the first set of one or more bridge wicking layers maybe coupled to a periphery or edge of at least one bridge wicking layerof the second set of one or more bridge wicking layers in any suitablemanner, such as, for example, by a weld 786, to define the internalvolume 760 of the bridge envelope 750. A bridge absorbent (such asbridge absorbent 354) may be positioned between the first set of one ormore bridge wicking layers and the second set of one or more bridgewicking layers. At least one bridge wicking layer of the first set ofone or more bridge wicking layers and at least one bridge wicking layerof the second set of one or more bridge wicking layers may each includethe fluid acquisition surface 772 and the fluid distribution surface774. The fluid distribution surface 774 may be positioned on an oppositeside of the at least one bridge wicking layer of the first set of one ormore bridge wicking layers and the at least one bridge wicking layer ofthe second set of one or more bridge wicking layers from the fluidacquisition surface 772. Further, the fluid distribution surface 774 ofthe at least one bridge wicking layer of the first set of one or morebridge wicking layers and the at least one bridge wicking layer of thesecond set of one or more bridge wicking layers may face the bridgeabsorbent (such as bridge absorbent 354). In some embodiments, at leasta portion of the bridge absorbent may be spaced apart or separated fromthe fluid distribution surface 774 of the at least one bridge wickinglayer of the first set of one or more bridge wicking layers and the atleast one bridge wicking layer of the second set of one or more bridgewicking layers.

In some embodiments, the internal passageway 784 may house a film, afirst wicking layer, a second wicking layer. The film may be a baselayer of adhesive coated polyurethane (PU) film. The adhesive coated onthe film may adhere the first wicking layer to an inner surface of thebridge sealing member 758. The first wicking layer may be stacked orplaced below or underneath the second wicking layer such that fluid(such a fluid of exudate) is communicated from the first wicking layerto the second wicking layer and out the conduit interface 148. The firstwicking layer may have a wider base and a higher density relative to thesecond wicking layer. The first wicking layer may have a greaterthickness (such as 50 mm) relative to the second wicking layer thickness(such as 20 mm). The first wicking layer may include a profile to spreadthe fluid out over an entire surface of the first wicking layer toincrease evaporation. The second wicking layer may be used to pull fluidfrom the wound towards to the conduit interface 148. In someembodiments, the second wicking layer may alternatively or additionallyinclude a profile like the profile of the first wicking layer to spreadfluid out over an entire surface of the second wicking layer. Theprofile of the second wicking layer may also be used to increaseevaporation.

The bridge sealing member 758 may define the internal passageway 784.The internal passageway 784 may be in fluid communication between thereceiving end 734 and the transmitting end 738 of the bridge 720. Insome embodiments, the bridge sealing member 758 may entirely surroundthe one or more wicking layers 754. In some embodiments, the bridgesealing member 758 may sealingly enclose the one or more wicking layers754 between the receiving end 734 and the transmitting end 738 of thebridge 720.

The bridge sealing member 758 may be comprised of similar materialsdescribed herein for the dressing sealing member 140. For example, insome embodiments, the bridge sealing member 758 may comprise asubstantially liquid impermeable film. Further, in some embodiments, thebridge sealing member 758 may comprise a vapor permeable film. Further,in some embodiments, the bridge sealing member 758 may comprise abreathable film. Additional examples of materials suitable for thebridge sealing member 758 may include, without limitation, apolyurethane (PU) drape or film such as Scapa Bioflex 130 polyurethaneFilm®; films formed from polymers, such as polyester and co-polyester;polyamide; polyamide/block polyether; acrylics; vinyl esters; polyvinylalcohol copolymers; films with and without adhesive; and high MoistureVapor Transfer Rate (MVTR) films, such as, for example, an INSPIRE 2305polyurethane drape. High MVTR films may provide for evaporation ofcondensate, which may occur around the entire exterior surface of thebridge 720. In this manner, capacity, fluid handling, and evaporativeproperties of the bridge 720 may be enhanced or improved due at least toincreased surface area and air movement provided around all sides andportions of the exterior surface of the bridge 720.

The bridge sealing member 758 may comprise a non-woven material orstructure such as, without limitation, a polyester, co-polyester,polyolefin, cellulosic fiber, and combinations or blends of theforegoing materials. In some embodiments, the bridge sealing member 758may comprise LIBELTEX TDL4 or LIBELTEX TDL2, or any of the materialsrecited above for the first dressing wicking layer 176 and the seconddressing wicking layer 180. Further, in some embodiments, the bridgesealing member 758 may comprise laminations with fiber or foamstructures.

In some embodiments, the bridge sealing member 758 may include the firstsealing layer 788 and the second sealing layer 790. A first periphery oredge of the first sealing layer 788 may be coupled to a second peripheryor edge of the second sealing layer 790 around the bridge envelope 750in any suitable manner, such as, for example, by a weld 792 for formingthe bridge sealing member 758 and encapsulating the bridge envelope 750therein. In other embodiments, the bridge sealing member 758 may beformed from a single layer of material.

In operation, the reduced-pressure source 128 may be fluidly coupled tothe receiving end 734 of the bridge 720. For example, the conduitinterface 148 may be fluidly coupled to the receiving end 734, and theconduit 196 may be fluidly coupled between the conduit interface 148 andthe reduced-pressure source 128 analogous to the previously describedembodiments. The transmitting end 738 of the bridge 720 may be fluidlycoupled to the dressing 124 as described herein. The reduced-pressuresource 128 may be activated to provide reduced pressure to the dressing124 through the bridge 720, which may draw, wick, or pull fluids fromthe tissue site 104 and the dressing 124 into the bridge 720.

As fluid enters the bridge 720 through the transmitting end 738, thefluid may communicate through the internal passageway 784 and contactthe fluid acquisition surface 772 of the first wicking layer 780. Thefluid acquisition surface 772 of the first wicking layer 780 may receivethe fluid so that the fluid may be transported through the first wickinglayer 780. Subsequently, the fluid distribution surface 774 of the firstwicking layer 780 may transmit the fluid from the first wicking layer780. In some embodiments, the fluid distribution surface 774 of thefirst wicking layer 780 may transmit the fluid directly to the receivingend 734. In some embodiments, the fluid distribution surface 774 of thefirst wicking layer 780 may transmit fluid into the internal volume 760.In some embodiments, the fluid distribution surface 774 of the firstwicking layer 780 may transmit the fluid to the receiving end 734through the internal volume 760. In some embodiments, the fluiddistribution surface 774 of the first wicking layer 780 may transmitfluid to the fluid acquisition surface 772 of the second wicking layer781.

As fluid is transmitted from the fluid distribution surface 774 of thefirst wicking layer 780, the fluid may contact the fluid acquisitionsurface 772 of the second wicking layer 781. The fluid acquisitionsurface 772 of the second wicking layer 781 may receive the fluid sothat the fluid may be transported through the second wicking layer 781.Subsequently, the fluid distribution surface 774 of the second wickinglayer 781 may transmit the fluid from the second wicking layer 781. Insome embodiments, the fluid distribution surface 774 of the secondwicking layer 781 may transmit the fluid directly to the receiving end734. In some embodiments, the fluid distribution surface 774 of thesecond wicking layer 781 may transmit fluid into the internal volume760. In some embodiments, the fluid distribution surface 774 of thesecond wicking layer 781 may transmit the fluid to the receiving end 734through the internal volume 760. In some embodiments, the fluiddistribution surface 774 of the second wicking layer 781 may transmitfluid to the fluid acquisition surface 772 of the third wicking layer782.

As fluid is transmitted from the fluid distribution surface 774 of thesecond wicking layer 781, the fluid may contact the fluid acquisitionsurface 772 of the third wicking layer 782. The fluid acquisitionsurface 772 of the third wicking layer 782 may receive the fluid so thatthe fluid may be transported through the third wicking layer 782.Subsequently, the fluid distribution surface 774 of the third wickinglayer 782 may transmit the fluid from the third wicking layer 782. Insome embodiments, the fluid distribution surface 774 of the thirdwicking layer 782 may transmit the fluid directly to the receiving end734.

Although the subject matter of this disclosure has been provided by wayof example in the context of certain illustrative, non-limitingembodiments, various changes, substitutions, permutations, andalterations can be made without departing from the scope of thisdisclosure as defined by the appended claims. Any feature described inconnection to any one embodiment may also be applicable to any otherembodiment. For example, an absorbent layer, such as absorbent layer 184discussed herein, may be included within the bridge assembly 710. Assuch, the benefits and advantages described above may relate to oneembodiment or may relate to several embodiments. Further, the steps ofthe methods described herein may be carried out in any suitable order,or simultaneously where appropriate.

It should be understood, that dressings as discussed herein may includeonly one or more wicking layers (i.e. a dressing without an absorbentlayer) and that a bridge as discussed herein in fluid communication withsuch dressing may include only one or more wicking layers (i.e. a bridgewithout an absorbent layer). It should also be understood, that thatdressings as discussed herein may include only one or more wickinglayers (i.e. a dressing without an absorbent layer) and that a bridge asdiscussed herein in fluid communication with such dressing may includeone or more wicking layers and an absorbent layer. In addition, itshould be understood, that dressings as discussed herein may include oneor more wicking layers and an absorbent layer and that a bridge asdiscussed herein in fluid communication with such dressing may includeonly one or more wicking layers (i.e. a bridge without an absorbentlayer).

Among other benefits described above, the storage bridge 320 may reducepower consumption, leakage, and other challenges that may be associatedwith fluid head pressure caused by a static column of fluid that canreside in a conventional tube or similar structure providing fluidcommunication between a dressing and a reduced-pressure source. Further,a mass of fluid removed from a tissue site may be moved away from thesurface of the tissue site. The storage bridge 320 may also provide alow-profile and conformable solution for providing fluid communicationwith a tissue site, which may enhance patient comfort.

In addition, a system with dressings and/or bridges with one or morewicking layers and without absorbents may provide a low profile dressingand bridge so that a patient may discretely wear such a system, forexample, by securing it to a tissue site with one or more bandages. Inaddition, a system with dressings and/or bridges with one or morewicking layers and without absorbents may be used with a manual pump orhand pump to remove fluid from a tissue site due to having relativelyless air taken to be taken up by a canister of or in fluid communicationwith the manual pump or hand pump. This may be due at least in part tothe low profile created by the one or more wicking layers. Further, asystem with dressings and/or bridges with one or more wicking layers andwithout absorbents may have relatively less head pressure when reducedpressure is applied by a manual pump or hand pump. A system withdressings and/or bridges with one or more wicking layers and withoutabsorbents may also extend the life of the system and increase mobilityby a patient.

What is claimed is:
 1. A bridge assembly for treating a tissue site, thebridge assembly comprising: a bridge comprising a receiving end and atransmitting end separated by a length, the bridge further comprising: abridge sealing member extending along the length of the bridge anddefining an internal passageway in fluid communication between thereceiving end and the transmitting end; and one or more bridge wickinglayers disposed within the internal passageway, the one or more bridgewicking layers configured to communicate fluid between the receiving endand the transmitting end of the bridge, wherein the one or more bridgewicking layers comprise a first bridge wicking layer and a second bridgewicking layer, wherein the first bridge wicking layer has a surface areathat is greater than a surface area of the second bridge wicking layer,and wherein the first bridge wicking layer is adapted to be positionedunderneath the second bridge wicking layer.
 2. The bridge assembly ofclaim 1, further comprising a bridge absorbent disposed within theinternal passageway, the bridge absorbent comprising a volume that isless than a volume of the internal passageway.
 3. The bridge assembly ofclaim 1, further comprising a conduit interface adapted to be fluidlycoupled to the receiving end of the bridge, the conduit interface influid communication with the transmitting end through the bridge.
 4. Thebridge assembly of claim 1, wherein the first bridge wicking layer has adensity that is greater than a density of the second bridge wickinglayer.
 5. The bridge assembly of claim 1, wherein the bridge sealingmember entirely surrounds the one or more bridge wicking layers.
 6. Thebridge assembly of claim 1, wherein the bridge sealing memberencapsulates the one or more bridge wicking layers.
 7. The bridgeassembly of claim 1, wherein the bridge sealing member comprises anon-woven material.
 8. The bridge assembly of claim 1, wherein the oneor more bridge wicking layers is moveable within the internalpassageway.
 9. The bridge assembly of claim 1, wherein the one or morebridge wicking layers further comprises a third bridge wicking layer,and wherein a periphery of the first bridge wicking layer is coupled toa periphery of the third bridge wicking layer, and wherein the secondbridge wicking layer is positioned between the first bridge wickinglayer and the third bridge wicking layer.
 10. The bridge assembly ofclaim 1, wherein each of the one or more bridge wicking layers iscomprised of a non-woven material.
 11. The bridge assembly of claim 1,wherein each of the one or more bridge wicking layers comprises a fluidacquisition surface and a fluid distribution surface positioned oppositethe fluid acquisition surface, wherein the fluid distribution surface ofeach of the one or more bridge wicking layers faces a first direction,and wherein the fluid acquisition surface of each of the one or morebridge wicking layers faces a second direction.
 12. The bridge assemblyof claim 1, wherein the bridge sealing member comprises a substantiallyliquid impermeable film.
 13. The bridge assembly of claim 1, wherein thebridge sealing member comprises a vapor permeable film.
 14. The bridgeassembly of claim 1, wherein the bridge sealing member comprises abreathable film.
 15. The bridge assembly of claim 1, wherein the bridgesealing member comprises a first sealing layer and a second sealinglayer, and wherein a periphery of the first sealing layer is coupled toa periphery of the second sealing layer around the one or more bridgewicking layers.
 16. A bridge assembly for treating a tissue site, thebridge assembly comprising: a bridge comprising a receiving end and atransmitting end separated by a length, the bridge further comprising: abridge sealing member extending along the length of the bridge anddefining an internal passageway in fluid communication between thereceiving end and the transmitting end; and a first bridge wicking layerand a second bridge wicking layer disposed within the internalpassageway and configured to communicate fluid between the receiving endand the transmitting end, wherein the first bridge wicking layer has adensity that is greater than a density of the second bridge wickinglayer, and wherein the first bridge wicking layer is adapted to bepositioned underneath the second bridge wicking layer.
 17. A bridgeassembly for treating a tissue site, the bridge assembly comprising: abridge comprising a receiving end and a transmitting end separated by alength, the bridge further comprising: a bridge sealing member extendingalong the length of the bridge and defining an internal passageway influid communication between the receiving end and the transmitting end;and one or more bridge wicking layers disposed within the internalpassageway and configured to communicate fluid between the receiving endand the transmitting end, wherein a periphery of one of the one or morebridge wicking layers is directly coupled to a periphery of another ofthe one or more bridge wicking layers to form an enclosure therebetween.18. A bridge assembly for treating a tissue site, the bridge assemblycomprising: a bridge comprising a receiving end and a transmitting endseparated by a length, the bridge further comprising: a bridge sealingmember extending along the length of the bridge and defining an internalpassageway in fluid communication between the receiving end and thetransmitting end; and one or more bridge wicking layers disposed withinthe internal passageway, the one or more bridge wicking layersconfigured to communicate fluid between the receiving end and thetransmitting end of the bridge, wherein the one or more bridge wickinglayers comprises a first bridge wicking layer, a second bridge wickinglayer, and a third bridge wicking layer, and wherein a periphery of thefirst bridge wicking layer is coupled to a periphery of the third bridgewicking layer, and wherein the second bridge wicking layer is positionedbetween the first bridge wicking layer and the third bridge wickinglayer.